Accessory, image pickup apparatus on which same is mountable, and camera system

ABSTRACT

An accessory configured to be detachably mountable to an image pickup apparatus including a first mount portion including first bayonet claw portions, and first terminals, the accessory including a second mount portion including second bayonet claw portions configured to enable engagement with the first bayonet claw portions, and second terminals configured to enable contact with the first terminals, in which the second terminals are provided at positions that are different from positions of the second bayonet claw portions, and wherein, a half line that extends from a central axis of the second mount portion and passes through a second terminal that determines whether an optical apparatus is mounted on the image pickup apparatus or not, passes through a predetermined second bayonet claw portion.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation, and claims the benefit, of U.S.patent application Ser. No. 15/992,785, filed May 30, 2018, which claimsthe benefit of Japanese Patent Application No. 2017-108262 filed May 31,2017. Each of U.S. patent application Ser. No. 15/992,785 and JapanesePatent Application No. 2017-108262 is hereby incorporated by referenceherein in its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present disclosure relates to an accessory, an image pickupapparatus on which the accessory is mountable, and a camera system.

Description of the Related Art

A camera and a camera accessory is described in U.S. Pat. No. 9,684,229,in which the camera includes a plurality of terminal pins. The documentalso discloses a camera accessory, such as an interchangeable lensassembly (an interchangeable lens) mountable with respect to the camera,that includes a plurality of terminal surfaces that come in contact withthe plurality of terminal pins to communicate with the camera.

The interchangeable lens assembly described in U.S. Pat. No. 9,684,229includes a plurality of bayonet claw portions capable of being connectedto a plurality of bayonet claw portions provided on a camera side. InU.S. Pat. No. 9,684,229, when the interchangeable lens assembly ismounted on the camera, a terminal surface on the interchangeable lensassembly side that comes in contact with a terminal pin, (among theplurality of terminal pins on the camera side that determines the typeof interchangeable lens assembly) is positioned within an angle range inwhich a predetermined bayonet claw portion on the interchangeable lensassembly side is provided. By including such a configuration, theinterchangeable lens assembly described in U.S. Pat. No. 9,684,229 iscapable of determining, in a more stable manner, the type ofinterchangeable lens assembly mounted on the camera.

We will now discuss a case wherein, other than the terminal pindescribed above (that determines the type of interchangeable lensassembly mounted on the camera), a terminal pin (MIF terminal, thatdetermines whether the interchangeable lens assembly has been mounted onthe camera), is provided in the plurality of terminal pins on the cameraside. When a terminal pin equivalent to a camera-side MIF terminal comesinto contact with a terminal surface equivalent to an MIF terminal onthe interchangeable lens assembly side, and when mounting of theinterchangeable lens assembly on the camera is detected, supply of powerfrom the camera to the interchangeable lens assembly is started andcommunication between the camera and the interchangeable lens assemblyis started. Accordingly, it is desirable that in a state in which theinterchangeable lens assembly is mounted on the camera, the terminal pinequivalent to the camera-side MIF terminal be in contact with theterminal surface equivalent to the MIF terminal on the interchangeablelens assembly side in a more stable manner. However, U.S. Pat. No.9,684,229 does not disclose a configuration having the terminal pinequivalent to the camera-side MIF terminal come into contact with theterminal surface equivalent to the MIF terminals on the interchangeablelens assembly side in a more stable manner.

SUMMARY OF THE INVENTION

Accordingly, the present disclosure provides an accessory in which aterminal on the image pickup apparatus side that determines whether theaccessory has been mounted on the image pickup apparatus is capable ofcoming in contact with a terminal on the accessory side in a more stablemanner, an image pickup apparatus on which the accessory can be mounted,and a camera system.

An accessory of the present disclosure is an accessory configured to bedetachably mountable to an image pickup apparatus including a firstmount portion including a plurality of first bayonet claw portions, anda plurality of first terminals, the accessory including a second mountportion including a plurality of second bayonet claw portions configuredto enable engagement with the plurality of first bayonet claw portions,and a plurality of second terminals configured to enable contact withthe plurality of first terminals, wherein the plurality of secondterminals are provided at positions that are different from positions ofthe plurality of second bayonet claw portions, and when viewed in acentral axis direction of the second mount portion, a half line thatextends from a central axis of the second mount portion and passesthrough a second terminal, among the plurality of second terminals, thatdetermines whether the accessory is mounted on the image pickupapparatus or not, passes through a predetermined second bayonet clawportion among the plurality of second bayonet claw portions.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings. Each of the embodiments of the present inventiondescribed below can be implemented solely or as a combination of aplurality of the embodiments. Also, features from different embodimentscan be combined where necessary or where the combination of elements orfeatures from individual embodiments in a single embodiment isbeneficial.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram of a camera and an interchangeable lensassembly according to an exemplary embodiment, and FIG. 1B is a blockdiagram of terminals of the camera and the interchangeable lens assemblyaccording to the exemplary embodiment.

FIG. 2A is an overall schematic view of the camera and theinterchangeable lens assembly according to the exemplary embodiment, andFIG. 2B is an overall schematic view illustrating a state in which theinterchangeable lens assembly according to the exemplary embodiment hasbeen dismounted from the camera.

FIG. 3A is an exploded perspective view of the camera according to thepresent exemplary embodiment, and FIG. 3B is an exploded perspectiveview of the interchangeable lens assembly according to the presentexemplary embodiment.

FIGS. 4A and 4B are detailed diagrams of a camera mount according to thepresent exemplary embodiment, and FIG. 4C is a cross sectional view of acamera mount according to the present exemplary embodiment.

FIG. 5A is a front view of the camera according to the present exemplaryembodiment in a normal position state, and FIG. 5B is a cross-sectionalview of the camera according to the present exemplary embodiment in thenormal position state taken along line VB-VB.

FIG. 6A is a front view of the camera according to the present exemplaryembodiment in a vertical position state, and FIG. 6B is across-sectional view of the camera according to the present exemplaryembodiment in the vertical position state taken along line VIB-VIB.

FIG. 7A is a front view of a lock phase state of a lens mount accordingto the present exemplary embodiment, and FIG. 7B is a cross-sectionalview of a lock phase state of a lens mount according to the presentexemplary embodiment in the vertical position state taken along lineVIIB-VIIB.

FIG. 8A is a detailed diagram illustrating a dispositional relationshipof a camera contact pin according to the present exemplary embodiment,FIG. 8B is a perspective view illustrating a dispositional relationshipof a camera contact pin according to the present exemplary embodiment.

FIG. 9A is a detailed diagram illustrating a dispositional relationshipof lens contact portions according to the present exemplary embodiment,FIG. 9B is a perspective view illustrating a dispositional relationshipof the lens contact portions according to the present exemplaryembodiment.

FIG. 10A is a diagram illustrating an insertion phase state when theinterchangeable lens assembly is attached to the camera according to thepresent exemplary embodiment viewed from the camera photographer side,and FIG. 10B is a diagram illustrating a lock phase state when theinterchangeable lens assembly is attached to the camera according to thepresent exemplary embodiment viewed from the camera photographer side.

FIG. 11 is a perspective view of the lens mount and a lens-side terminalholding member.

FIG. 12 is an exploded perspective view of a mount mechanism accordingto a modification.

FIGS. 13A to 13C are drawings illustrating a mount mechanism accordingto the modification in a non-connected state.

FIGS. 14A to 14C are diagrams illustrating the mount mechanism accordingto the modification in a connected state.

FIGS. 15A and 15B are diagrams describing a first conversion adapterthat is mountable to the camera body, and a second interchangeable lensassembly.

FIGS. 16A and 16B are diagrams describing a second conversion adapterthat is mountable to a camera body, and the first interchangeable lensassembly.

FIGS. 17A through 17C is a diagram for exemplarily describing angle sodisposing bayonet claw portions in a camera mount provided on one end ofthe first conversion adapter.

FIGS. 18A and 18B are diagrams exemplarily describing angle so disposingbayonet claw portions in the lens mount provided on the other end of thefirst conversion adapter.

FIGS. 19A and 19B are diagrams exemplarily describing a mounting methodof a predetermined imaging apparatus and a predetermined interchangeablelens assembly having claw portions and recesses that interfere with eachother.

FIGS. 20A and 20B are diagrams exemplarily describing the way in whichclaw portions interfere with each other when attempting to mount thelens mount side to the camera mount side according to an embodiment ofthe present invention.

FIGS. 21A through 21D is a diagram exemplarily describing a case ofattempting to insert incompatible claw portions into recesses at thelens mount side and camera mount side according to an embodiment of thepresent invention.

FIGS. 22A and 22B are diagrams exemplarily describing angle so disposingbayonet claw portions in the camera mount provided on one end of thesecond conversion adapter.

FIGS. 23A through 23C are diagrams exemplarily describing angle sodisposing bayonet claw portions in a lens mount provided on the otherend of the second conversion adapter.

FIGS. 24A and 24B are diagrams exemplarily describing the way in whichclaw portions interfere with each other, when attempting to mount areference claw at the lens mount side to a reference recess at thecamera mount side according to an embodiment of the present invention.

FIGS. 25A through 25D are diagrams exemplarily describing the way inwhich claw portions interfere with each other, when attempting to mounta claw other than the reference claw at the lens mount side to areference recess at the camera mount side according to an embodiment ofthe present invention.

FIG. 26 is a diagram exemplarily describing a state in which clawportions provided to the camera mount side and lens mount side accordingto an embodiment of the present invention are engaged.

DESCRIPTION OF THE EMBODIMENTS

Configuration of Camera System

Referring first to FIG. 1A, a camera system that is an exemplaryembodiment of the present disclosure will be described. As illustratedin FIG. 1A, the camera system according to the present exemplaryembodiment includes an interchangeable lens assembly (an opticalapparatus, an accessory, a lens apparatus) 100 that is a cameraaccessory, and a camera body (an image pickup apparatus) 10 on which theinterchangeable lens assembly 100 is detachably mounted. In other words,the interchangeable lens assembly 100 can be mounted and dismounted fromthe camera body 10.

Configuration of Interchangeable Lens Assembly 100

The interchangeable lens assembly 100 includes a lens 101, and a lensdrive unit 102 including an actuator that moves and operates opticalmembers, such as a lens unit and an aperture (both not shown), includedin the lens 101. Furthermore, the interchangeable lens assembly 100includes a lens control unit 103 including a microcomputer that controlscommunication between a camera control unit 18 through a mount 1 andthat controls the lens drive unit 102. Note that the lens 101 mayinclude only a single lens unit or may include a plurality of lens unit.The same applies to the aperture.

Herein, the lens unit is a term denoting a single lens element, a singlecemented lens, or a collective plurality of lenses, in which an intervalwith an adjacent lens unit changes when zooming or focusing.Furthermore, the lens 101 includes a zooming lens unit that is a lensunit that moves in an optical axis direction to perform zooming, and afocusing lens unit that moves in the optical axis direction to performfocusing. The lens 101 further includes a shift lens unit that moves indirections different from the optical axis direction to perform camerashake correction. Note that the lens 101 does not have to include thezooming lens unit and the shift lens unit.

Configuration of Camera Body 10

The camera body 10 includes an image sensor (an image pickup element) 11that is a charge-storage type solid-state image pickup element thatoutputs an electric signal after photoelectrically converting an imageof a subject, which is an optical image formed by the lens 101 in theinterchangeable lens assembly 100. The camera body 10 further includesan A/D conversion unit 12 that converts an analog electrical signaloutput from the image sensor 11 into a digital signal, and an imageprocessor 13 that generates an image signal by performing various typesof image processing on the digital signal converted by the A/Dconversion unit 12.

The image signal (a still image or a moving image) generated with theimage processor 13 is displayed on a display unit 14 or is recorded in arecording medium 15. Furthermore, the camera body 10 includes a memory16 that functions as a buffer when processing is performed on the imagesignal. The memory 16 stores an operation program used by the cameracontrol unit 18 described later. The camera body 10 further includes acamera operation input unit 17 including a power switch that turns thepower source on and off, a photographing switch that starts recording ofan image signal, and a selecting/setting switch to perform setting ofvarious menus.

The camera body 10 further includes the camera control unit 18 thatincludes a microcomputer. The camera control unit 18 performs varioussettings based on signals input from the camera operation input unit 17,and controls the communication between the lens control unit 103included in the interchangeable lens assembly 100 through the mount 1.

Configuration of Electrical Connection Between Camera Body 10 andInterchangeable Lens Assembly 100

Referring next to FIG. 1B, a configuration of the electrical connectionbetween the camera body 10 and the interchangeable lens assembly 100will be described. FIG. 1B illustrates an electric circuit configurationwhen the camera body 10 and the interchangeable lens assembly 100 areconnected to each other through the mount 1, terminals (electricalcontacts) provided in the mount 1 to electrically connect the camerabody 10 and the interchangeable lens assembly 100 to each other, and astate in which the terminals are connected to each other.

The mount 1 in the camera system includes a mount portion (a first mountportion) A on the camera body 10 side and a mount portion (a secondmount portion) B on the interchangeable lens assembly 100 side. Themount portion A and the mount portion B include a plurality of terminals(contact points or electrical contacts) that are capable of beingelectrically connected to the counterparts. More specifically, the mount1 includes VDD terminals and VBAT terminals that supply power to theinterchangeable lens assembly 100 from the camera body 10, DGNDterminals and PGND terminals that are ground terminals. The mount 1further includes LCLK terminals, DCL terminals, DLC terminals, DLC2terminals, CS terminals, and DCA terminals that are communicationterminals for the camera control unit 18 and the lens control unit 103to communicate with each other. As other terminals, the mount 1 furtherincludes MIF terminals that detect that the interchangeable lensassembly 100 has been mounted on the camera body 10, and TYPE terminalsthat distinguish the type of camera accessory that has been mounted onthe camera body 10. Hereinafter, a more detailed description of theterminals will be given.

Power Terminals

The VDD terminals are terminals that supply communication control power(VDD), which is communication power used mainly to controlcommunication, to the interchangeable lens assembly 100 from the camerabody 10. In the present exemplary embodiment, the communication controlpower is 5.0 V. The VBAT terminals are terminals that supply drivingpower (VBAT), which is driving power used in operations other than theabove communication control, such as operations of mechanical drivesystems and the like mainly including a motor and the like, to theinterchangeable lens assembly 100 from the camera body 10. In thepresent exemplary embodiment, the driving power is 4.25 V.

Ground Terminals

The DGND terminals are terminals that connect the camera body 10 and thecommunication control system of the interchangeable lens assembly 100 tothe ground. In other words, the DGND terminals are ground (GND)terminals corresponding to the VDD power source described above.Grounding herein is setting to a level that is the same as the level ofthe negative electrode-side of the power source such as a battery. ThePGND terminals are terminals that connect the camera body 10 and themechanical drive system, such as a motor, provided in theinterchangeable lens assembly 100 to the ground. In other words, thePGND terminals are grounding (GND) terminals that correspond to the VBATpower source described above.

Communication Terminals

The communication terminals include a terminal unit (the LCLK, DCL, andDLC terminals) that is a first communication unit that performs thefirst communication, and terminals (the DLC2 terminals) that are asecond communication unit that performs the second communicationindependent of the first communication. The communication terminalsfurther include a terminal unit (the CS, and DCA terminals) that is athird communication unit that performs the third communicationindependent of the first and second communications. The camera controlunit 18 and the lens control unit 103 are capable of performing thefirst, second, and third communications that are independent of eachother through the above communication terminals.

The LCLK terminals are terminals for communication clock signals outputfrom the camera body 10 to the interchangeable lens assembly 100, andare also terminals in which the camera body 10 monitors a busy state ofthe interchangeable lens assembly 100. The DCL terminals are terminalsfor two-way communication data between the camera body 10 and theinterchangeable lens assembly 100, and are CMOS interfaces. The DLCterminals are terminals for communication data that is output from theinterchangeable lens assembly 100 to the camera body 10, and are CMOSinterfaces.

The DLC2 terminals are terminals for communication data that is outputfrom the interchangeable lens assembly 100 to the camera body 10, andare CMOS interfaces. The DCA terminals are terminals for two-waycommunication data between the camera body 10 and the interchangeablelens assembly 100, and are CMOS interfaces. The CS terminals areterminals for a communication request signal between the camera body 10and the interchangeable lens assembly 100, and are open interfaces.

Other Terminals

MIF terminals are terminals for detecting whether the interchangeablelens assembly 100 has been mounted on the camera body 10, and whetherthe interchangeable lens assembly 100 has been dismounted from thecamera body 10. After detecting that the interchangeable lens assembly100 has been mounted on the camera body 10 by detecting the change inthe voltage level of the MIF terminals, the camera control unit 18starts supplying power to the VDD terminals and the VBAT terminals, andstarts communication. In other words, the MIF terminals are triggersthat start the supply of power from the camera body 10 to theinterchangeable lens assembly 100.

As described above, the TYPE terminals are terminals that distinguishthe type of camera accessory mounted on the camera body 10. The cameracontrol unit 18 detects the voltages of the signals of the TYPEterminals, and based on the value of the voltages, distinguishes thetype of camera accessory mounted on the camera body 10. Theinterchangeable lens assembly 100 is pull-down connected to the DGNDterminals at a predetermined resistance value described later. In thepresent exemplary embodiment, in a case in which the interchangeablelens assembly 100 is mounted on the camera body 10, communication isperformed while the interface voltages of the first communication unit,the second communication unit, and the third communication unit are setto 3.0 V.

Configuration of Mechanical Connection Between Camera Body 10 andInterchangeable Lens Assembly 100

FIGS. 2A and 2B are perspective views of external appearances of thecamera body 10 and the interchangeable lens assembly 100. FIG. 2Aillustrates a state in which the interchangeable lens assembly 100 ismounted on the camera body 10. FIG. 2B illustrates a state in which theinterchangeable lens assembly 100 has been dismounted from the camerabody 10. The camera body 10 and the interchangeable lens assembly 100are connected to each other by moving the interchangeable lens assembly100 in the unlocking position to the locking position while referencesurfaces of a camera mount 201 and a lens mount 301 are in contact witheach other. Note that herein, the camera mount 201 is a mount portion (afirst mount portion) on an image pickup apparatus side, and the lensmount 301 is a mount portion (a second mount portion) on an opticalapparatus side. Note that in the following description, a secondconversion adapter 70 has a camera mount 1201 same as the camera mount201 of the camera body 10. And, note that in the following description,a first conversion adapter 40 has a lens mount 1301 same as the lensmount 301 of the first lens 100. And note that the camera mount 201 andthe lens mount 301 have the ring-shaped, but this is not restrictive inthe present embodiments. For example, a configuration may be employedwhere this is realized by each of the camera mount 201 and lens mount301 have an arc-shaped contact faces, may be employed in theconfiguration. In other words, a configuration may be employed wherethis is realized by the camera mount 201 and the lens mount 301 arelacked a part of the contact face.

FIGS. 3A and 3B are exploded perspective views of the camera body 10 andthe interchangeable lens assembly 100. FIG. 3A illustrates an explodedperspective view of the camera body 10, and FIG. 3B illustrates anexposed perspective view of the interchangeable lens assembly 100. Anoptical axis 3000 is an optical axis of the lens 101 included in theinterchangeable lens assembly 100, and in a state in which theinterchangeable lens assembly 100 is mounted on the camera body 10, alight flux for imaging passing along the optical axis 3000 can enter theimage sensor 11.

Members Included in Camera Body 10

Members included in the camera body 10 will each be described next.

A lock pin 202 is a restriction member (a locking member, a convexportion) that restricts (locks) a mounted state of the camera body 10and the camera accessory. Note that the lock pin 202 can be advanced andretreated in a direction parallel to the optical axis 3000.Specifically, when the interchangeable lens assembly 100 is mounted onthe camera body 10, the lock pin 202 enters a lock pin groove (a concaveportion, a groove portion, a recess) 301 z of the lens mount 301 to lockthe state in which the interchangeable lens assembly 100 and the camerabody 10 are locked to each other.

A holding member 203 is a camera-side terminal holding member that holdsa plurality of terminal pins 203 a to 203 k, and 203 m provided on thecamera body 10 side.

A camera body member 204 is a camera housing that holds the members ofthe camera body 10. Specifically, the camera mount 201 and the holdingmember 203 described above are fastened to the camera body member 204with fastening screws 205 a to 205 d for the camera mount 201 andfastening screws for the holding member 203 (not shown). Note that thecamera body member 204 holds an image pickup unit (not shown) on whichthe image sensor 11 is mounted and a shutter unit (not shown).

A lens mount biasing member 206 is a camera-side biasing member thatdraws in described-later first to third lens claw portions (a pluralityof second engagement portions and a plurality of second bayonet clawportions) 301 d to 301 f provided in the lens mount 301 towards a cameramount 201 side. The lens mount biasing member 206 is interposed in aspace between the camera mount 201 and the camera body member 204.

Members Included in Interchangeable Lens Assembly 100

Members included in the interchangeable lens assembly 100 will each bedescribed next.

A front lens 101 a and a rear lens 101 b are optical members included inthe lens 101. Naturally, the lens 101 may include lenses other than thefront lens 101 a and the rear lens 101 b.

The lens mount 301 is a mount portion on the interchangeable lensassembly 100 side. A lens barrel (an accessory main body) 302 is a lensholding member that holds the lens 101. The lens mount 301 is fastenedto the lens barrel 302 with lens mount fastening screws (mount fixingmembers) 304 a to 304 d.

A holding member 303 is a lens-side terminal holding member that holds aplurality of terminal surfaces 303 a to 303 k, and 303 m provided on theinterchangeable lens assembly 100 side. The holding member 303 is fastedto the lens mount 301 with lens contact portion holding portionfastening screws 305 a and 305 b.

Configuration of Camera Mount 201

Referring next to FIGS. 4A to 6B, a configuration of the camera mount201 will be described.

FIGS. 4A and 4B are drawings of the camera mount 201 viewed from aphotographer side (a rear side of the camera body 10) of the camera body10. FIG. 5A is a drawing illustrating a normal position state, which isa state most frequently used when the interchangeable lens assembly 100is mounted on the camera body 10. In the normal position state, a cameragrip 204 a of the camera body 10 is positioned on the left side whenviewed from a subject side.

FIG. 5B is a partially enlarged cross-sectional view of the camera body10 taken along line VB-VB. In FIG. 5B, the interchangeable lens assembly100 is mounted and the camera body 10 is in the normal position state.Line VB-VB extends in the vertical direction that passes the middle ofthe camera mount 201. FIG. 6A is a drawing illustrating a verticalposition state, which is a state used second most frequently withrespect to the normal position state when the interchangeable lensassembly 100 is mounted on the camera body 10. In the vertical positionstate, the camera body 10 is set so that the camera grip 204 a is on theupper side (the lock pin 202 being positioned on the lower side when thecamera mount 201 is viewed from the photographer side). FIG. 6B is apartially enlarged cross-sectional view of the camera body 10 takenalong line VIB-VIB. In FIG. 6B, the interchangeable lens assembly 100 ismounted and the camera body 10 is in the vertical position state. LineVIB-VIB passes the middle of the camera mount 201, extends in thevertical direction, and is orthogonal to line VB-VB.

As illustrated in FIGS. 4A and 4B, a plurality of camera claw portionsare provided in the camera mount 201. The plurality of camera clawportions are a plurality of first engagement portions (a plurality offirst bayonet claw portions) included in the camera mount 201 and eachhave widths in a radial direction and a circumferential direction of theopening. The plurality of camera claw portions herein are a first cameraclaw portion (a camera-side bayonet claw portion) 201 a, a second cameraclaw portion 201 b, and a third camera claw portion 201 c.

In FIGS. 4A and 4B, a space between the first camera claw portion 201 aand the second camera claw portion 201 b is referred to as a firstcamera cutaway (a first camera concave portion, a first camera recess)201 d, and a space between the second camera claw portion 201 b and thethird camera claw portion 201 c is referred to as a second cameracutaway 201 e. Furthermore, a space between the third camera clawportion 201 c and the first camera claw portion 201 a is referred to asa third camera cutaway 201 f.

Herein, two ends of the first camera claw portion 201 a are referred toas a first end 201 a 1 and a second end 201 a 2, and two ends of thesecond camera claw portion 201 b are referred to as a third end 201 b 1and a fourth end 201 b 2. Furthermore, two ends of the third camera clawportion 201 c are referred to as a fifth end 201 c 1 and a sixth end 201c 2.

Furthermore, an angle formed by a line connecting a center of the cameramount 201 and the first end 201 a 1, and a line connecting the center ofthe camera mount 201 and the second end 201 a 2 is assumed to be θa. Anangle formed by a line connecting the center of the camera mount 201 andthe third end 201 b 1, and a line connecting the center of the cameramount 201 and the fourth end 201 b 2 is assumed to be θb. Furthermore,an angle formed by a line connecting the center of the camera mount 201and the fifth end 201 c 1, and a line connecting the center of thecamera mount 201 and the sixth end 201 c 2 is assumed to be θc. Asillustrated in FIGS. 4A and 4B, in the present exemplary embodiment,θa=48°, θb=40°, θc=92° are satisfied. Each of θa, θb, and θc are anglesof the corresponding camera claw portions in the circumferentialdirection.

Furthermore, assuming that an angle formed by the line connecting thecenter of the camera mount 201 and the second end 201 a 2, and the lineconnecting the center of the camera mount 201 and the third end 201 b 1is an angle of the first camera cutaway 201 d in the circumferentialdirection, the above angle is 57° in the present exemplary embodiment.Similarly, an angle of the second camera cutaway 201 e in thecircumferential direction is 66°, an angle of the third camera cutaway201 f in the circumferential direction is 57°.

Furthermore, a line segment connecting the center of the camera mount201 and a center of the lock pin 202 is referred to as a reference line.Furthermore, an angle in which the first camera claw portion 201 a isdisposed is assumed to be in the range of an angle formed between theline connecting the center of the camera mount 201 and the first end 201a 1 and the reference line to an angle formed between the lineconnecting the center of the camera mount 201 and the second end 201 a 2and the reference line. The angle in which the first camera claw portion201 a is disposed is in the range of 169° to 217°. Similarly, an anglein which the second camera claw portion 201 b is disposed is in therange of 274° to 314°, and an angle in which the third camera clawportion 201 c is disposed is in the range of 20° to 112°.

Herein, θa is divided by a center line 3002 that is a line that passesthe center of the lock pin 202 and the center of the camera mount 201into an angle θa1 on the upper side of the center line 3002 and an angleθa2 on the lower side. In the present exemplary embodiment, the cameraclaw portions and the camera cutaways are disposed so that relationshipsθc≥θa+θb, and θa1+θc>θa2+θb are satisfied.

By employing such a configuration, the strength of the camera clawportion above the center line 3002 of the camera mount 201, or thecenter line 3002 that extends in the horizontal direction, can beincreased. Accordingly, in the camera body 10 in the normal positionstate on which the interchangeable lens assembly 100 has been mounted,deformation of the camera claw portions supporting the weight of theinterchangeable lens assembly 100 can be suppressed and tilting of theinterchangeable lens assembly 100 in the vertical direction can bereduced.

Furthermore, in the present exemplary embodiment, the third camera clawportion 201 c is disposed so that a center line 3003 passing the centerof the camera mount 201 passes at least a portion of third camera clawportion 201 c when the camera body 10 is in the normal position state.The center line 3003 passing the center of the camera mount 201 is aline orthogonal to the center line 3002 that passes the center of thelock pin 202 and the center of the camera mount 201. The center line3003 extends in the vertical direction from a center axis parallel withthe optical axis 3000. In other words, the center line 3003 is avertical line that passes though the center axis of the camera mount 201and orthogonal to the center axis of the camera mount 201 when thecamera body 10 is placed on a horizontal plane.

With the above configuration, as illustrated in FIG. 5B, in the normalposition state, a space Δ1, described later, in a direction parallel tothe optical axis 3000 between the third lens claw portion 301 f and thethird camera claw portion 201 c can be reduced. Accordingly, when thecamera body 10 and the interchangeable lens assembly 100 are in thenormal position state, the space created by the interchangeable lensassembly 100 in the gravity direction 4000 (a direction orthogonal tothe optical axis 3000) with the camera body 10 while the camera mount201 supports the weight of the interchangeable lens assembly 100 can bereduced.

Furthermore, in the present exemplary embodiment, the first camera clawportion 201 a is disposed so that the center line 3002 passing thecenter of the camera mount 201 when the camera body 10 is in the normalposition state passes at least a portion of the first camera clawportion 201 a.

With the above configuration, as illustrated in FIG. 6B, in the verticalposition state, a space Δ2 in a direction parallel to the optical axis3000 between the first lens claw portion 301 d and the first camera clawportion 201 a can be reduced. Accordingly, in the camera body 10 in thevertical position state on which the interchangeable lens assembly 100has been mounted, the space created by the interchangeable lens assembly100 in the gravity direction 4000 with the camera body 10 while thecamera mount 201 supports the weight of the interchangeable lensassembly 100 can be reduced.

Configuration of Lens Mount 301

A configuration of the lens mount 301 will be described with referenceto FIGS. 7 to 9B.

FIG. 7 is a diagram of the lens mount 301 of the interchangeable lensassembly 100, viewed from the photographer side, in a state (a lockphase state) in which the lens mount 301 is locked to the camera body 10that is in the normal position state, which is a state in which the lockpin groove 301 z is positioned on the left side when viewed from thephotographer side.

The lens mount 301 are provided with the first lens claw portion (alens-side bayonet claw portion) 301 d, the second lens claw portion 301e, and the third lens claw portion 301 f as a plurality of secondengagement portions having widths in the radial direction and thecircumferential direction of the opening included in the lens mount 301.The lens mount 301 is further provided with a circumferential-directionpositioning pin 301 y that prevents the interchangeable lens assembly100 from rotating excessively from the desired position when theinterchangeable lens assembly 100 is mounted on the camera body 10. Byhaving the positioning pin 301 y come in contact with the fourth end 201b 2, the interchangeable lens assembly 100 is stopped from rotating pastthe desired position described above.

Referring to FIG. 7, a space between the third lens claw portion 301 fand the first lens claw portion 301 d is referred to as a first lenscutaway 301 a, and a space between the first lens claw portion 301 d andthe second lens claw portion 301 e is referred to as a second lenscutaway 301 b. Furthermore, a space between the second lens claw portion301 e and the third lens claw portion 301 f is referred to as a thirdlens cutaway 301 c.

Furthermore, two ends of the first lens claw portion 301 d are referredto as a first end 301 d 1 and a second end 301 d 2, and two ends of thesecond lens claw portion 301 e are referred to as a third end 301 e 1and a fourth end 301 e 2. Furthermore, two ends of the third lens clawportion 301 f are referred to as a fifth end 301 f 1 and a sixth end 301f 2.

As illustrated in FIG. 7, an angle of the first lens claw portion 301 din the circumferential direction is 53°, an angle of the second lensclaw portion 301 e in the circumferential direction is 62°, and an angleof the third lens claw portion 301 f in the circumferential direction is53°. The angle of the first lens claw portion 301 d in thecircumferential direction herein is an angle formed between a lineconnecting a center of the lens mount 301 and the first end 301 d 1, anda line that connects the center of the lens mount 301 and the second end301 d 2. The angles of the second lens claw portion 301 e and the thirdlens claw portion 301 f in the circumferential direction can be definedin a similar manner to the definition of the angle of the first lensclaw portion 301 d in the circumferential direction.

Furthermore, assuming that an angle formed by a line connecting thecenter of the lens mount 301 and the fifth end 301 f 1, and a lineconnecting the center of the lens mount 301 and the first end 301 d 1 isan angle of the first lens cutaway 301 a in the circumferentialdirection, the above angle is 52° in the present exemplary embodiment.Similarly, an angle of the second lens cutaway 301 b in thecircumferential direction is 44°, an angle of the third lens cutaway 301c in the circumferential direction is 96°.

Furthermore, a line segment connecting the center of the lens mount 301and a center of the lock pin groove 301 z is referred to as a referenceline. Furthermore, an angle in which the first lens claw portion 301 dis disposed is assumed to be in the range of an angle formed between theline connecting the center of the lens mount 301 and the first end 301 d1 and the reference line to an angle formed between a line connectingthe center of the lens mount 301 and the second end 301 d 2 and thereference line. The angle in which the first lens claw portion 301 d isdisposed is in the range of 159° to 212°. Similarly, an angle in whichthe second lens claw portion 301 e is disposed is in the range of 256°to 318°, and an angle in which the third lens claw portion 301 f isdisposed is in the range of 54° to 107°.

Note that in the normal position state, a center line that passes thecenter of the lens mount 301 and that is orthogonal to a center line3006 that passes the center of the lock pin groove 301 z and the centerof the lens mount 301 is referred to as a center line 3005. The centerline 3005 passes at least a portion of the second lens claw portion 301e and at least a portion of the third lens claw portion 301 f. With theabove, deformation of the lens claw portions due to the above-describedspace Δ1 illustrated in FIG. 5B and the interchangeable lens assembly100 attempting to tilt in the vertical direction can be reduced. Thecenter line 3005 is a vertical line that passes through a center axis ofthe lens mount 301 and orthogonal to the center axis of the lens mount301 when the camera body 10 which is attached the interchangeable lensassembly 100 is placed on a horizontal plane.

Furthermore, the first lens claw portion 301 d is disposed so that thecenter line 3006 passes at least a portion of the first lens clawportion 301 d. With the above, deformation of the lens claw portions dueto the above-described space Δ2 illustrated in FIG. 6B and theinterchangeable lens assembly 100 attempting to tilt in the verticaldirection can be reduced.

Dispositional Relationship Between Camera Mount 201 and Camera-SideTerminals

Referring next to FIGS. 8A and 8B, the dispositional relationshipbetween the camera mount 201 and camera-side terminals described abovewill be described.

FIG. 8A is a diagram of the dispositional relationship between thecamera mount 201, the plurality of terminal pins 203 a to 203 k, and 203m that are the plurality of camera-side terminals (first terminals), andthe holding member 203 viewed from the subject side (a front side of thecamera body 10). FIG. 8B is a diagram of the camera mount 201, theterminal pins 203 a to 203 k, and 203 m, and the holding member 203viewed from obliquely above and from the subject side (the front side ofthe camera body 10).

As illustrated in FIG. 8A, in the holding member 203, the terminal pins203 a to 203 k, and 203 m are arranged on a camera terminal pinarrangement line 3001. The terminal pins 203 a to 203 k, and 203 m areeach a movable terminal that can be advanced and retreated in adirection parallel to the optical axis 3000, and are biased towards theinterchangeable lens assembly 100 side with springs (not shown).

The relationship between the terminals illustrated in FIG. 1B describedabove and the terminal pins is as follows. In other words, the terminalpin 203 a is the camera-side VDD terminal, the terminal pin 203 b is thecamera-side VBAT terminal, the terminal pin 203 c is the camera-sideTYPE terminal, the terminal pin 203 d is the camera-side PGND terminal,and the terminal pin 203 e is the camera-side MIF terminal. Furthermore,the terminal pin 203 f is the camera-side DCL terminal, the terminal pin203 g is the camera-side DLC terminal, the terminal pin 203 h is thecamera-side LCLK terminal, the terminal pin 203 i is the camera-sideDLC2 terminal, and the terminal pin 203 j is the camera-side DCAterminal. Furthermore, the terminal pin 203 k is the camera-side CSterminal, the terminal pin 203 m is the camera-side DGND terminal.

As illustrated in FIG. 8B, heights of the terminal pins 203 a, 203 b,203 c, and 203 d in an optical axis 3000 direction are higher thanheights of the terminal pins 203 e, 203 f, 203 g, 203 h, 203 i, 203 j,203 k, and 203 m in the optical axis 3000 direction. The above isbecause the holding member 203 includes two surfaces that have differentheights in the optical axis 3000 direction in which the terminal pins203 a, 203 b, 203 c, and 203 d are provided in the higher surface andthe rest of the terminal pins are provided in the lower surface.

In other words, all of the terminal pins of the present exemplaryembodiment are not provided in surfaces at the same height. By havingsuch a configuration, the present exemplary embodiment is capable ofsuppressing abrasion of the terminals caused by the camera-sideterminals sliding against the lens-side terminals when theinterchangeable lens assembly 100 is mounted on the camera body 10. Morespecifically, when the interchangeable lens assembly 100 is rotated fromthe locking position to the unlocking position to mount theinterchangeable lens assembly 100 on the camera body 10, there is aperiod in which the terminal pins 203 e to 203 k, and 203 m are not incontact with the lens-side terminals. Accordingly, the abrasion of theterminals described above can be suppressed.

Relationship Between Lens Mount 301 and Lens-Side Terminals

Referring next to FIGS. 9A and 9B, the dispositional relationshipbetween the lens mount 301 and lens-side terminals described above willbe described. FIG. 9A is a diagram of the dispositional relationshipbetween the lens mount 301 in which the interchangeable lens assembly100 is in the lock phase state, the terminal surfaces 303 a to 303 k,and 303 m that are the plurality of lens-side terminals (secondterminals), and the holding member 303 viewed from the photographerside. FIG. 9B is a diagram of the lens mount 301, the terminal surfaces303 a to 303 k, and 303 m, and the holding member 303 viewed fromobliquely above from the photographer side in a case in which theinterchangeable lens assembly 100 is in the lock phase state and inwhich the interchangeable lens assembly 100 is mounted on the camerabody 10.

As illustrated in FIG. 9A, in the holding member 303, the terminalsurfaces 303 a to 303 k, and 303 m are arranged on a lens contact pointarrangement line 3004. The relationship between the terminalsillustrated in FIG. 1B described above and the terminal surfaces is asfollows. In other words, the terminal surface 303 a is the lens-side VDDterminal, the terminal surface 303 b is the lens-side VBAT terminal, theterminal surface 303 c is the lens-side TYPE terminal, the terminalsurface 303 d is the lens-side PGND terminal, and the terminal surface303 e is the lens-side MIF terminal.

Furthermore, the terminal surface 303 f is the lens-side DCL terminal,the terminal surface 303 g is the lens-side DLC terminal, the terminalsurface 303 h is the lens-side LCLK terminal, the terminal surface 303 iis the lens-side DLC2 terminal, and the terminal surface 303 j is thelens-side DCA terminal. Furthermore, the terminal surface 303 k is thelens-side CS terminal, and the terminal surface 303 m is the lens-sideDGND terminal.

As illustrated in FIG. 9B, heights of the terminal surfaces 303 a, 303b, 303 c, and 303 d in the optical axis 3000 direction are lower thanheights of the terminal surfaces 303 e, 303 f, 303 g, 303 h, 303 i, 303j, 303 k, and 303 m in the optical axis 3000 direction. The above isbecause the holding member 303 includes two surfaces that have differentheights in the optical axis 3000 direction in which the terminalsurfaces 303 a, 303 b, 303 c, and 303 d are provided on the lowersurface and the rest of the terminal surfaces are provided on the highersurface. By having the lens-side terminals have the above configurationthat corresponds to the configuration of the camera-side terminalsdescribed above, the abrasion of the terminals described above can besuppressed.

Reference numerals 303 n and 303 p are guiding inclined faces (inducingoblique surfaces) for mounting the interchangeable lens assembly 100 onthe camera body 10 by pushing the terminal pins towards the image sensor11 side when the interchangeable lens assembly 100 is rotated. Byproviding the guiding inclined faces, the contact pressure against thelens mount 301 of the terminal pins provided on the camera body 10 sidechanges in a gentle and stepwise manner; accordingly, deformation of theterminal pins provided on the camera body 10 side can be reduced.

Operation of Attaching Interchangeable Lens Assembly 100 on Camera Body10

Referring next to FIGS. 10A and 10B, an operation of fitting theinterchangeable lens assembly 100 on the camera body 10 will bedescribed.

The operation of mounting a camera accessory, such as theinterchangeable lens assembly 100, on the camera body 10 can be broadlyseparated into a first operation and a second operation described next.

The first operation is an operation in which the interchangeable lensassembly 100 is inserted into the camera body 10 by setting thepositions of the camera body 10 and the interchangeable lens assembly100 to predetermined positions in the rotation direction so as to allowthe lens claw portions enter the camera cutaways and is an operation inwhich a lens-side diameter fitting portion 301 x in FIG. 7B and acamera-side diameter fitting portion 201 x in FIG. 4C are diametricallyfitted to each other. Furthermore, the second operation is an operationin which, while the lens-side diameter fitting portion 301 x and thecamera-side diameter fitting portion 201 x are diametrically fitted toeach other, relatively rotating the camera body 10 and theinterchangeable lens assembly 100 towards the locking position, and isan operation bringing the camera body 10 and the interchangeable lensassembly 100 to a bayonet coupled state.

FIG. 10A is a diagram illustrating an insertion phase state (a firststate) when the camera body 10 is attached to the interchangeable lensassembly 100 of the present exemplary embodiment viewed from the cameramount 201 side (the photographer side). Note that the insertion phasestate refers to a state in which the first lens claw portion 301 d isinserted in the first camera cutaway 201 d, the second lens claw portion301 e is inserted in the second camera cutaway 201 e, and the third lensclaw portion 301 f is inserted in the third camera cutaway 201 f. Thelens-side diameter fitting portion 301 x and the camera-side diameterfitting portion 201 x are diametrically fitted to each other in theabove state.

FIG. 10B is a diagram illustrating a lock phase state (a second state)when the camera body 10 is attached to the interchangeable lens assembly100 of the present exemplary embodiment viewed from the camera mount 201side (the photographer side). Note that the lock phase state is a statein which the interchangeable lens assembly 100 is, from the insertionphase state illustrated in FIG. 10A described above, rotated 60° in theclockwise direction when viewed from the subject side of theinterchangeable lens assembly 100 to engage the lens claw portions andthe camera claw portions to each other.

More specifically, in the lock phase state, the first lens claw portion301 d is positioned on the image sensor 11 side of the first camera clawportion 201 a, and the second lens claw portion 301 e is positioned onthe image sensor 11 side of the second camera claw portion 201 b.Furthermore, the third lens claw portion 301 f is positioned on theimage sensor 11 side of the third camera claw portion 201 c. The lensclaw portions and the camera claw portions are engaged with each otherin the above state, and the lock pin 202 is inserted in the lock pingroove 301 z; accordingly, rotation of the interchangeable lens assembly100 is locked. Furthermore, in the lock phase state, the lens clawportions are biased towards the image sensor 11 with the lens mountbiasing member 206. Note that in place of the lens mount biasing member206, a flat spring portion may be provided in each camera claw portion.

Furthermore, when the interchangeable lens assembly 100 is transitionedfrom the insertion phase state to the lock phase state, the terminalpins on the camera body 10 side are pressed towards the image sensor 11side with the guiding inclined faces 303 n and 303 q described above.

Furthermore, while being continuously pressed, each of the terminal pinson the camera body 10 side come in contact with the correspondingterminal surfaces 303 a to 303 k, and 303 m. Note that the terminal pin203 m and the terminal surface 303 e come in contact with each otherfirst.

Dispositional Relationship Between Lens Claw Portions and Lens-Side MIFTerminals

As illustrated in FIG. 9A, in the present exemplary embodiment, theterminal surface 303 e, which is the lens-side MIF terminal, is insidean angle range C that is where the second lens claw portion 301 e isprovided. The angle range C herein is, viewed in the direction in whichthe optical axis 3000 extends (viewed in a central axis direction of theoptical apparatus), a range between a half line extending from theoptical axis 3000 (the central axis of the optical apparatus) andpassing the third end 301 e 1, and a half line extending from theoptical axis 3000 and passing the fourth end 301 e 2. The terminalsurfaces 303 e being inside angle range C, which is where the secondlens claw portion 301 e is provided, can be paraphrased as bellow. Inother words, in a case in which, when viewed in the optical axis 3000direction, a first line is assumed to be a half line in which theoptical axis 3000 is an end thereof and is a half line that passes thethird end 301 e 1, and a second line is assumed to be a half line inwhich the optical axis 3000 is and end thereof and is a half line thatpasses the fourth end 301 e 2, the terminal surface 303 e is in theregion surrounded by the outer periphery of the lens-side diameterfitting portion 301 x, the first line, and the second line. Note thatthe expression of angle ranges D and E described later can beparaphrased in a similar manner to angle range C described above.

As described above, the MIF terminal is a terminal that detects that theinterchangeable lens assembly 100 has been mounted on the camera body10. Furthermore, when it is detected with the MIF terminal that theinterchangeable lens assembly 100 has been mounted on the camera body10, supply of power to the VDD terminal and the VBAT terminal is startedand communication between the camera body 10 and the interchangeablelens assembly 100 is started. Accordingly, it is desirable that theterminal pin 203 e that is the MIF terminal on the camera side and theterminal surface 303 e that is the MIF terminal on the lens side are incontact with the counterparts in a stable manner.

Accordingly, in the present exemplary embodiment, the camera-side MIFterminal, which determines whether the interchangeable lens assembly 100has been mounted on the camera body 10, can be in contact with thelens-side MIF terminal in a more stable manner with the configurationdescribed above illustrated in FIG. 9A. Since the camera-side MIFterminal and the lens-side MIF terminal are in contact with each otherin a stable manner, communication between the camera body 10 and theinterchangeable lens assembly 100 can be stated in a stable manner.Furthermore, operation of the communication protocol between the camerabody 10 and the interchangeable lens assembly 100 becomes stable andhigh-speed communication can be performed.

As described above, according to the present exemplary embodiment,communication between the camera body 10 and the interchangeable lensassembly 100 can be performed in a stable manner. As a result, throughfurther increase in the communication speed, usability of the camerabody 10 and the interchangeable lens assembly 100 can be improved andnew pieces of information can be exchanged between the camera body 10and the interchangeable lens assembly 100; accordingly, a new functioncan be added to the camera system.

Note that the terminal surfaces 303 e, which is a lens-side MIFterminal, being inside angle range C, which is where the second lensclaw portion 301 e is provided, can be paraphrased as bellow. In otherwords, as illustrated in FIG. 9A, when viewed in the central axisdirection of the lens mount 301, a half line that passes the terminalsurface 303 e, which is the lens-side MIF terminal, and the central axisof the lens mount 301 passes the second lens claw portion 301 e, whichis a predetermined second bayonet claw portion.

Furthermore, when the accessory is the interchangeable lens assembly,the central axis of the lens mount 301 may be the optical axis of theinterchangeable lens assembly, or may be the central axis of the openingof the lens mount 301.

Furthermore, as illustrated in FIG. 9A, in the present exemplaryembodiment, the plurality of lens-side terminals are provided atpositions that are different from those of the plurality of lens-sidebayonet claw portions. More specifically, while the plurality oflens-side bayonet claw portions are positioned outside the openingincluded in the lens mount 301, the plurality of lens-side terminals arepositioned inside the opening.

Dispositional Relationship Between Lens Claw Portions and Lens-SideCommunication Terminals

In the present exemplary embodiment, in addition to the terminal surface303 e that is the lens-side MIF terminal, the lens-side communicationterminals are also provided inside angle range C that is where thesecond lens claw portion 301 e is provided. The lens-side communicationterminals herein are the terminal surface 303 f, the terminal surface303 g, the terminal surface 303 h, the terminal surface 303 i, theterminal surface 303 j, and the terminal surface 303 k. As illustratedin FIG. 9A, in the present exemplary embodiment, all of theabove-described lens-side communication terminals are inside angle rangeC, which is where the second lens claw portion 301 e is provided. Withsuch a configuration, when the interchangeable lens assembly 100 isattached to the camera body 10, the lens-side communication terminalsare positioned in the region or near the region that is stable due tothe bayonet coupling between the camera claw portions and the lens clawportions. Accordingly, when imaging is actually carried out,communication between the interchangeable lens assembly 100 and thecamera body 10 can be performed in a further stable manner. Note that inthe present exemplary embodiment, all of the lens-side communicationterminals are inside angle range C, which is where the second lens clawportion 301 e is provided. However, for example, it is only sufficientthat half or more of the lens-side communication terminals, morepreferably, 80 percent or more thereof are inside angle range C, wherethe second lens claw portion 301 e is provided.

Note that all of the above-described lens-side communication terminalsbeing inside angle range C, where the second lens claw portion 301 e isprovided, can be paraphrases as follows. In other words, as illustratedin FIG. 9A, when viewed in the central axis direction of the lens mount301, half lines that pass the plurality of lens-side communicationterminals and the central axis of the lens mount 301 all pass the secondlens claw portion 301 e, which is a predetermined second bayonet clawportion.

Furthermore, as illustrated in FIGS. 9A and 9B, in the present exemplaryembodiment, a length of the holding member 303, which is a lens-sideterminal holding portion, in the circumferential direction is longerthan a length of a single lens-side bayonet claw portion. Accordingly,all of the lens-side terminals cannot be disposed inside angle range C.Accordingly, in the present exemplary embodiment, as described above,the terminal surface 303 e, which is the lens-side MIF terminal that isespecially important, and all of the lens-side communication terminalsare priority disposed inside angle range C.

Dispositional Relationship Between Lens Claw Portions and PositioningPin 303 p

Referring next to FIG. 11, a dispositional relationship between the lensclaw portions and the positioning pin (a protrusion) 303 p will bedescribed.

The positioning pin 303 p is provided in the holding member 303, and isa pin that extends outwardly in the radial direction of the openingincluded in the lens mount 301. By inserting the positioning pin 303 pin a hole portion 301 h 3 provided in the lens mount 301, the positionof the holding member 303 with respect to the lens mount 301 isdetermined. In a state in which the positioning pin 303 p is inserted inthe hole portion 301 h 3, by using hole portions 301 h 2 and 301 h 4provided in the lens mount 301 and screws (not shown), the holdingmember 303 can be fixed to the lens mount 301. Note that a hole portion301 hl is a hole portion in which the positioning pin 301 y describedabove is inserted to suppress the interchangeable lens assembly 100 fromrotating past the desired position. Note that in the present exemplaryembodiment, the hole portions are through holes; however, for example,the hole portion 301 h 3 may be a recess with a bottom and does not haveto be a through hole as long as the hole portion 301 h 3 engages withthe positioning pin 303 p.

As described above, in the present exemplary embodiment, the terminalsurface 303 e, which is the lens-side MIF terminal, is inside an anglerange C that is where the second lens claw portion 301 e is provided. Inaddition to the above, as illustrated in FIG. 11, in the presentexemplary embodiment, the positioning pin 303 p is also inside anglerange C (FIG. 9A), where the second lens claw portion 301 e is provided.With such a configuration, when the interchangeable lens assembly 100 isattached to the camera body 10, the positioning pin 303 p is positionedin the region or near the region that is stable due to the bayonetcoupling between the camera claw portions and the lens claw portions.Accordingly, when imaging is actually carried out, in a case in whichexternal force such as a vibration or an impact when dropped is appliedto the interchangeable lens assembly 100 or the camera body 10,deviation in the position of the holding member 303 can be suppressed.

Note that the above-described positioning pin 303 p as well as beinginside angle range C, where the second lens claw portion 301 e isprovided, can also be described as follows. In other words, when viewedin the central axis direction of the lens mount 301, a half line thatpasses the positioning pin 303 p and the central axis of the lens mount301 passes the second lens claw portion 301 e, which is a predeterminedsecond bayonet claw portion.

Dispositional Relationship Between Terminal Surface 303 e andPositioning Pin 303 p

Furthermore, as described above, when the interchangeable lens assembly100 transitions from the insertion phase state to the lock phase state,the first terminal pin and the terminal surface that come into contactwith each other are the terminal pin 203 m and the terminal surface 303e. Accordingly, when the interchangeable lens assembly 100 is attachedto the camera body 10, it is desirable that the terminal surface 303 eis stable. Accordingly, in the present exemplary embodiment, theterminal surface 303 e is provided near to the positioning pin 303 p inthe circumferential direction of the lens mount 301. With the abovearrangement, when the interchangeable lens assembly 100 transitions fromthe insertion phase state to the lock phase state, the terminal surface303 e, which is the terminal surface that comes in contact with theterminal pin first, and the terminal pin are in contact with each otherin a more stable manner.

As described above, the terminal surface 303 e being provided near thepositioning pin 303 p, can also be described as follows. In other words,in an interchangeable lens assembly 100 in the normal position state(the lock pin groove 301 z on the left side), the positioning pin 303 pis provided within the angle range D between a line passing a center ofthe terminal surface 303 d and the optical axis 3000, and a line passinga center of the terminal surface 303 g and the optical axis 3000. Notethat the terminal surface 303 d is a terminal surface next to theterminal surface 303 e in an anticlockwise direction, and the terminalsurface 303 g is a terminal surface that is two terminal surfaces nextto the terminal surface 303 e in the clockwise direction. Furthermore,it is desirable that positioning pin 303 p be positioned in angle rangeE between a line passing a center of the terminal surface 303 e and theoptical axis 3000, and a line passing the center of the terminal surface303 g and the optical axis 3000.

The dispositional relationship between the terminal surface 303 e andthe positioning pin 303 p can also be described as follows. In otherwords, while having the terminal surface 303 e that is a lens-side MIFterminal as a reference terminal, among the plurality of lens-sideterminals, a lens-side terminal that is, when viewed from the terminalsurface 303 e, nearest to the terminal surface 303 e in a firstdirection (the anticlockwise direction in FIG. 9A) is referred to as afirst adjacent terminal. In the present exemplary embodiment, the firstadjacent terminal is the terminal surface 303 d. Furthermore, among theplurality of lens-side terminals, a lens-side terminal that is, whenviewed from the terminal surface 303 e, nearest to the terminal surface303 e in a second direction (the clockwise direction in FIG. 9A), whichis a direction opposite to the first direction, is referred to as asecond adjacent terminal. In the present exemplary embodiment, thesecond adjacent terminal is the terminal surface 303 f. Furthermore,among the plurality of lens-side terminals, a lens-side terminal that isnearest to the second adjacent terminal in the second direction isreferred to as a third adjacent terminal. In the present exemplaryembodiment, the third adjacent terminal is the terminal surface 303 g.

In the above description, the positioning pin 303 p and the hole portion301 h 3 are inside angle range D from the terminal surface 303 d to theterminal surface 303 g. Furthermore, more preferably, the positioningpin 303 p and the hole portion 301 h 3 (FIG. 11) are inside angle rangeE from the terminal surface 303 e to the terminal surface 303 g (FIG.9A). The angle range D herein is, when viewed in the optical axis 3000direction, a half line extending from the optical axis 3000 and passingthe center of the terminal surface 303 d, and a half line extending fromthe optical axis 3000 and passing the center of the terminal surface 303g. Using the optical axis 3000, the center of the terminal surface 303e, and the center of the terminal surface 303 g, angle range E can bedefined in a similar manner to angle range D.

The dispositional relationship above can also be described as follows.In other words, when viewed in the central axis direction of the lensmount 301, the positioning pin 303 p and the hole portion 301 h 3 areinside a region between a half line that passes the central axis of thelens mount 301 and the first adjacent terminal, and a half line thatpasses the central axis of the lens mount 301 and the third adjacentterminal.

Furthermore, when viewed in the central axis direction of the lens mount301, the positioning pin 303 p and the hole portion 301 h 3 are inside aregion between a half line that passes the central axis of the lensmount 301 and the reference terminal, and a half line that passes thecentral axis of the lens mount 301 and the third adjacent terminal.

Note that the center of the terminal surface is, when the terminalsurface is rectangular, an intersection of the two diagonal lines of theterminal surface when viewed in the optical axis direction. In a case inwhich the terminal surface is rectangular, or is not rectangular and hasa round shape, or the like, the center of the terminal surface may be,when viewed in the optical axis direction, the center of gravity of theterminal surface.

Furthermore, in the present exemplary embodiment, as illustrated inFIGS. 9A, 9B, and 11, the terminal surface 303 c that is the lens-sideTYPE terminal is not inside angle range C. In other words, when viewedin the central axis direction of the lens mount 301, a half line thatpasses the terminal surface 303 c that is the lens-side TYPE terminalthat distinguishes the type of accessory mounted on the camera, and thecentral axis of the lens mount 301 passes the cutaway between theplurality of second bayonet claw portions.

Modifications

While a preferable embodiment of the present disclosure has beendescribed above, the present disclosure is not limited to the embodimentand may be deformed and modified within the gist of the presentdisclosure.

For example, in the present exemplary embodiment, the configuration ofthe interchangeable lens assembly 100 has been described by exemplifyingan interchangeable lens assembly 100 serving as the optical apparatus;however, the optical apparatus of the present disclosure is not limitedto the interchangeable lens assembly 100. For example, an adapter thatcan be interposed between the interchangeable lens assembly 100 and thecamera body 10 may serve as the optical apparatus (the accessory) of thepresent disclosure, and a mount of the adapter on the interchangeablelens assembly 100 side may be the mount having the same configuration asthat of the interchangeable lens assembly 100. Whether in theinterchangeable lens assembly 100, or in the adapter, a member to whichthe lens mount 301 is fixed with the fastening screws 304 a to 304 d isreferred to as the accessory main body.

Furthermore, in the present exemplary embodiment, a configuration inwhich the holding member 303 includes the positioning pin 303 p, and thelens mount 301 includes the hole portion 301 h 3 has been described.However, the present disclosure is not limited to such a configuration,and the holding member 303 may include a hole portion or a recess, andthe lens mount 301 may include a protrusion that engages with the holeportion or the recess. In other words, between the holding member 303and the lens mount 301, either one may include a protrusion, and theother one may include a hole portion or a recess.

Furthermore, the three bayonet claw portions provided in the mounts inthe exemplary embodiment described above may each be divided so as to befurther divided into segments. In other words, a single bayonet clawportion may be formed as a collection of a plurality of bayonet clawportions (a group of bayonet claw portions). For example, the abovecorresponds to a case in which a groove portion is provided in a singlebayonet claw portion. In such a case, the angle range of the group ofbayonet claw portions arranged in the circumferential direction of eachmount is as in the exemplary embodiment described above.

Furthermore, in the exemplary embodiment described above, aconfiguration has been described in which a device that includes eitherone of the camera mount and the accessory mount is actually rotatedrelative to a device that includes the other one of the camera mount andthe accessory mount to bayonet couple the devices to each other;however, the configuration is not limited to the above configuration.For example, a configuration that allows the camera mount and theaccessory mount to be bayonet coupled to each other by having the cameramount and the accessory mount be relatively rotated against each othermay be employed. Hereinafter, the detail of the above will be describedspecifically.

FIG. 12 is an exploded perspective view of a mount mechanism 5000according to a modification of the present disclosure. FIGS. 13A to 13Care diagrams that exemplify a non-connected state of the mount mechanism5000 according to the modification of the present disclosure. FIGS. 14Ato 14C are diagrams that exemplify a connected state of the mountmechanism 5000 according to the modification of the present disclosure.Note that in FIGS. 12 to 14C, for the sake of description, a movablemount portion 5010 of the mount mechanism 5000, and a lens mount 301that is capable of being bayonet coupled to the movable mount portion5010 of the mount mechanism 5000 are illustrated at the same time.Furthermore, description of members that are the same as those of theexemplary embodiment is omitted and the same reference numerals areattached to the members.

As illustrated in FIG. 12, in the mount mechanism 5000 of the presentmodification, an operation portion 5030, a fixed mount portion 5020, themovable mount portion 5010, a contact point holding member 203 that havean optical axis 3000 as the central axis are disposed in that order fromthe side on which the lens mount 301 is attached. The operation member5030 is a ring-shaped operation member rotatable about the central axis,and is connected to the movable mount portion 5010 with arm portions5040 and screws. Note that in the present modification, the operationportion 5030 and the movable mount portion 5010 are fixed to each otherat two portions using two arm portions 5040 disposed in a directionorthogonal to the central axis. With the above configuration, themovable mount portion 5010 is also rotated about the central axis inaccordance with the rotating operation of the operation portion 5030 inan integrated manner.

Movable mount claw portions 5011 a, 5011 b, and 5011 c capable of beingbayonet coupled to bayonet claw portions 301 a to 301 c provided in thelens mount 301 are provided in the movable mount portion 5010.Furthermore, a screw portion 5012 threaded about the central axis isprovided in the movable mount portion 5010. The state in which the screwportion 5012 and a screw portion 5022 of the fixed mount portion 5020described later are screwed to each other changes in accordance with therotation of the movable mount portion 5010 about the central axis.

The fixed mount portion 5020 includes a camera mount surface 5021 thatabuts against a mount surface of the lens mount 301, and the screwportion 5022 that is screwed to the screw portion 5012 of the movablemount portion 5010 described above. Different from the movable mountportion 5010 described above, the fixed mount portion 5020 does notrotate about the central axis in accordance with the rotating operationof the operation portion 5030.

Referring next to FIGS. 13A to 14C, a bayonet coupling method of themount mechanism according to the present modification will be described.Note that while in a state in which the bayonet claw portions areinserted in an opening portion of the operation member 5030 and anopening portion of the fixed mount portion 5020, the bayonet clawportions provided on the lens mount 301 are engageable with the movablemount claw portions 5011 a to 5011 c of the movable mount portion 5010.In the state illustrated in FIGS. 13A to 13C, the operation portion 5030is positioned in the unlocking position. In the above state, while alens mount surface of the lens mount 301 and the camera mount surface5021 of the fixed mount portion 5020 abut against each other, the clawportions of the lens mount 301 and the claw portions of the movablemount portion 5010 do not engage or overlap each other when viewed inthe central axis direction. FIG. 13C is a cross-sectional diagram takenalong cross-section XIIIC-XIIIC in FIG. 13B. FIGS. 14A to 14C illustratean exemplification of the mount mechanism 5000 in a state in which therotation operation has been performed on the operation portion 5030 fromthe above state.

In the state illustrated in FIGS. 14A to 14C, the operation portion 5030is positioned in the locking position. In the above state, when viewedin the central axis direction, the claw portions of the lens mount 301and the claw portions of the movable mount portion 5010 overlap eachother to engage with each other in the central axis direction. FIG. 14Cis a cross-sectional diagram taken along cross-section XIVC-XIVC in FIG.14B. As illustrated in FIGS. 13C and 14C, the movable mount portion 5010moves away from the fixed mount portion 5020 in a center axis directionof the mount depend on a non-locking state of the mount mechanism 5000changing in a lock state of the mount mechanism 5000. Furthermore, inthe above state, in accordance with the rotating operation of theoperation member 5030, the state in which the screw portion 5022 of thefixed mount portion 5020 and the screw portion of the movable mountportion 5010 are screwed to each other changes and the movable mountportion 5010 moves in the central axis direction towards the imagepickup apparatus side. With the above configuration, the movable mountclaw portions 5011 a to 5011 c engaged with the bayonet claw portions onthe lens mount 301 side each move towards the image pickup apparatusside.

As described above, in the mount mechanism 5000 of the presentmodification, by having the movable mount portion including the clawportions that can be engaged with the claw portions on the lens mountside be rotated about the central axis, the movable mount portion can bemoved in the central axis direction relative to the fixed mount portion.With such a configuration, in a state in which the lens mount and thecamera-side mount are connected to each other, the mount mechanism 5000of the present modification can reduce the occurrence of the gap (thespace) created between the lens mount and the camera-side mount.

Note that in the modification described above, a configuration in whichthe mount mechanism 5000 is provided on the image pickup apparatus sidehas been described; however, the present disclosure can be applied to,for example, a configuration in which the mount mechanism 5000 isprovided on the camera accessory side such as the interchangeable lensassembly side.

As described above, for example, in the present exemplary embodiment,the configuration of the interchangeable lens assembly 100 has beendescribed by exemplifying an interchangeable lens assembly 100 servingas the optical apparatus; however, the optical apparatus of the presentdisclosure is not limited to the interchangeable lens assembly 100. Forexample, an adapter that can be interposed between the interchangeablelens assembly 100 and the camera body 10 may serve as the opticalapparatus (the accessory) of the present disclosure. Hereinafter, a moredetailed description of this adapter will be given.

Firstly, the basic configuration of a conversion adapter (adapterdevice) that is a camera accessory mountable to the camera mount 201 ofthe above-described camera body 10 will be described with reference toFIGS. 15A through 16B. FIGS. 15A and 15B are diagrams describing a firstconversion adapter 40 that is mountable to the camera body 10, and asecond interchangeable lens assembly 50. FIG. 15A illustrates anexternal perspective view of the second interchangeable lens assembly 50having been mounted to the camera body 10 via the first conversionadapter 40. FIG. 15B illustrates an external perspective view of a statewhere the camera body 10, first conversion adapter 40, and secondinterchangeable lens assembly 50 have each been detached. Note that thesecond interchangeable lens assembly (hereinafter referred to as secondlens) 50 has a lens mount 501 that is short in flange focal distance,but has the same mount diameter as the camera mount 201, as to thecamera body 10. That is to say, the second lens 50 has the same mountdiameter as the above-described first lens 100, but unlike the firstlens 100, is a camera accessory that is not compatible with directmounting to the camera body 10.

FIGS. 16A and 16B are diagrams for describing a second conversionadapter 70 that is mountable to a camera body 60 and the first lens 100.FIG. 16A illustrates an external perspective view of a state where thefirst lens 100 is mounted to the camera body 60 via the secondconversion adapter 70, and FIG. 16B illustrates an external perspectiveview where the camera body 60, second conversion adapter 70, and firstlens 100 have each been detached.

Now, in a case where an interchangeable lens assembly with a long flangefocal distance is directly mounted to an imaging apparatus with a shortflange focal distance, trouble will occur such as the focal point notbeing formed at an accurate position or the like, and imaging a subjectin this way will result in an unnatural image being obtained. Forexample, the above problem will occur if the second lens 50 that has along flange focal distance is mounted to the above-described camera body10.

In the same way, in a case where an interchangeable lens assembly with ashort flange focal distance is directly mounted to an imaging apparatuswith a long flange focal distance, trouble will occur such as the focalpoint not being formed at an accurate position or the like, and imaginga subject in this way will result in an unnatural image being obtained.For example, the above problem will occur if the first lens 100 that hasa short flange focal distance is mounted to the camera body 60 servingas a second imaging apparatus that has a longer flange focal distancethan the above-described camera body 10.

Particularly, the camera body 10 and camera body 60, and the first lens100 and second lens 50, have the same mount diameter, it is difficultfor a user to judge which imaging apparatuses and which interchangeablelens assemblies have flange focal distances that are compatible fordirect mounting.

Accordingly, it is preferable that only interchangeable lens assembliesthat are compatible can be directly mounted to a certain imagingapparatus, so that imaging apparatuses and interchangeable lensassemblies that have mutually incompatible flange focal distances arenot erroneously directly mounted.

Also, in a case of mounting an incompatible interchangeable lensassembly to an imaging apparatus, a conversion adapter needs to beinterposed between the two to adjust the flange focal distance. However,in a case where one side of the conversion adapter is mounted to theimaging apparatus and an interchangeable lens assembly compatible withdirect mounting to the imaging apparatus is mounted to the other side ofthe conversion adapter, the focal point may not be accurately formed, asdescribed above. Accordingly, the one side and other side of theconversion adapter preferably have configurations to restrict imagingapparatuses and camera accessories that are directly mountable.

Specifically, in a case of mounting an interchangeable lens assemblyhaving a long flange focal distance to an imaging apparatus having ashort flange focal distance, a conversion adapter is preferable whereone end side is only mountable to this imaging apparatus, and the otherend side is only mountable to this interchangeable lens assembly. Also,in a case of mounting an interchangeable lens assembly having a shortflange focal distance to an imaging apparatus having a long flange focaldistance, a conversion adapter is preferable where one end side is onlymountable to this imaging apparatus, and the other end side is onlymountable to this interchangeable lens assembly.

The first conversion adapter 40 has the lens mount 1301 attached to anadapter barrel 40 a by fastening screws (omitted from illustration), atone end side in the optical axis direction. This lens mount 1301 is anaccessory mount that is detachable from the camera mount 201 provided tothe camera body 10 described above.

A camera mount 1401 is attached to the adapter barrel 40 a by fasteningscrews (omitted from illustration), at the other end side of the firstconversion adapter 40 in the optical axis direction. This camera mount1401 is a camera mount that is detachable from the lens mount 501 of thesecond lens 50. Note that the camera mount 1401 of the first conversionadapter 40 is attached so that the imaging plane of the imaging sensor11 of the will be situated at a position corresponding to the flangefocal distance of the second lens 50.

The second conversion adapter 70 has the lens mount 1501 attached to anadapter barrel 70 a by fastening screws (omitted from illustration), atone end side in the optical axis direction. This lens mount 1501 is anaccessory mount that is detachable from the camera mount 401 provided tothe camera body 60.

The camera mount 1201 is attached to the adapter barrel 70 a byfastening screws (omitted from illustration), at the other end side ofthe second conversion adapter 70 in the optical axis direction. Thiscamera mount 1201 is a camera mount that is detachable from the lensmount 301 of the first lens 100, as described above.

Note that a first optical member 701 a and a second optical member 701 bare provided to the second conversion adapter 70, between the adapterbarrel 70 a and the lens mount 1501 in the optical axis direction. Thefirst optical member 701 a and second optical member 701 b enable thesecond conversion adapter 70 to extend length of the flange focaldistance of the first lens 100 in accordance with the imaging plane ofthe imaging sensor disposed in the camera body 60. While the opticalmembers have been illustrated as two lenses for the sake of convenience,this is not restrictive.

Next, the angles (phases) at which bayonet claw portions are disposed onthe circumferential direction of the camera mount and lens mount of thefirst conversion adapter 40 will be described with reference to FIG. 17Athrough FIG. 21D. FIGS. 17A through 21D are diagrams for exemplarilydescribing displacement angles of bayonet claw portions in the cameramount 1401 provided on one end of the first conversion adapter 40. FIG.17A is a diagram illustrating angle ranges that camera claw portions andcamera cutaways occupy in the circumferential direction of the cameramount 1401 with the lock pin 1401 z as a reference, as viewed from therear face side (camera body 10 side). FIG. 17B is a diagram illustratingangle ranges that multiple camera claw portions 1401 a through 1401 coccupy in the circumferential direction of the camera mount 1401, asviewed from the rear face side (camera body 10 side). FIG. 17C is across-sectional diagram taken along cross-section XVIIB-XVIIB in FIG.17B.

The first conversion adapter 40 is a mount adapter used for mounting thesecond lens 50 that has a long flange focal distance to the camera body10 that has a short flange focal distance. Accordingly, it is preferablefor the first conversion adapter 40 to be configured such that thecamera body 60 that has a long flange focal distance cannot be directlymounted to the lens mount 1301, and the first lens 100 that has a shortflange focal distance cannot be directly mounted to the camera mount1401. According to this configuration, the positional relation of clawportions and cutaways can be satisfied so that the lens mount 1301provided to one end (first end) of the first conversion adapter 40 andthe camera mount 1401 provided to the other end (second end) cannot eachbe directly mounted.

A first camera claw portion 1401 a, second camera claw portion 1401 b,and third camera claw portion 1401 c, are provided in order, to thecamera mount 1401 in the circumferential direction (inner radialdirection). When viewing the camera mount 1401 from the rear face sideas illustrated in FIG. 17A, the camera claw portion that is provided ata position farthest from the lock pin 1401 z is the first camera clawportion 1401 a. The second camera claw portion 1401 b and third cameraclaw portion 1401 c are then consecutively provided in order from thefirst camera claw portion 1401 a in a clockwise direction.

Also, cutaways which are a first camera cutaway 1401 d, second cameracutaway 1401 e, and third camera cutaway 1401 f are provided in order,to the camera mount 1401 in the circumferential direction (inner radialdirection). When viewing the camera mount 1401 from the rear face sideas illustrated in FIG. 17A, the cutaway that is provided at a positionnearest to the lock pin 1401 z is the second camera cutaway 1401 e. Thethird camera cutaway 1401 f and first camera cutaway 1401 d are thenconsecutively provided in order from the second camera cutaway 1401 e ina clockwise direction.

As illustrated in FIG. 17C, a fitting member 1401 x that restrictsmovement of the camera accessory in a direction parallel to the opticalaxis when the camera accessory is mounted, is provided to the cameramount 1401 side. In the present embodiment, the diameter of the fittingmember 1401 x in a direction orthogonal to the optical axis at thecamera mount 1401 side is the mount diameter.

The way of bayonet coupling of the first conversion adapter 40 andsecond lens 50 is the generally the same as the way of bayonet couplingof the camera body 10 and first lens 100 described above, so descriptionwill be omitted.

Note that the end portions of the camera claw portions 1401 a, 1401 b,and 1401 c, in the circumferential direction, will be referred to asfirst end portion 1401 a 1, second end portion 1401 a 2, third endportion 1401 b 1, fourth end portion 1401 b 2, fifth end portion 1401 c1, and end portion 1401 c 2, for the sake of description. The endportions are denoted with part numerals in order from the first cameraclaw portion 1401 a in the clockwise direction, when viewing the cameramount 1401 from the rear face side, as described above.

As illustrated in FIG. 17A, the angles that the camera claw portions andcamera cutaways occupy in the circumferential direction of the cameramount 1401 (angle ranges) in the first conversion adapter 40 accordingto the present embodiment are stipulated as follows. For the firstcamera claw portion 1401 a, the angle θA1=56°, for the second cameraclaw portion 1401 b, the angle θA2=62°, and for the third camera clawportion 1401 c, the angle θA3=62°. Also, for the first camera cutaway1401 d, the angle is 57°, for the second camera cutaway 1401 e, theangle is 66°, and for the third camera cutaway 1401 f, the angle is 57°.That is to say the camera mount 1401 has different angles for the cameraclaw portions with respect to the above-described camera mount 201 ofthe camera body 10, but the angles of the camera cutaways are the same.

Also, when viewing the camera claw portions from the rear face side ofthe first conversion adapter 40, the angles where the camera clawportions are disposed on the circumferential direction of the cameramount 1401 with the position of the lock pin 402 (referred to asreference position) as a reference are stipulated as follows. The firstcamera claw portion 1401 a is disposed between 159° to 215° with thereference position as a start point. The second camera claw portion 1401b is disposed between 272° to 334° with the reference position as astart point. The third camera claw portion 1401 c is disposed between40° to 102° with the reference position as a start point.

Next, FIGS. 18A and 18B are diagrams exemplarily describing angles ofdisposing the bayonet claw portions on the lens mount 1301 provided tothe other end of the first conversion adapter 40. FIG. 18A is a diagramillustrating angle ranges that camera claw portions and camera cutawaysoccupy in the circumferential direction of the camera mount 1401 withthe lock groove 1301 z as a reference, as viewed from the rear faceside. FIG. 18B is a diagram illustrating angle ranges that multiple lenscutaways 1301 a through 1301 c occupy in the circumferential directionof the lens mount 1301, as viewed from the rear face side.

The angles (angle ranges) that the lens cutaways occupy in thecircumferential direction of the lens mount 1301 are, represented by θA4as the angle of the first lens cutaway 1301 a and θA5 as the angle ofthe second lens cutaway 1301 b, as illustrated in FIG. 18B. Note thatthe angle so disposing the claw portions and cutaways on the lens mount1301 of the first conversion adapter 40 is the same as the lens mount301 of the first lens 100 described above, and accordingly descriptionwill be omitted.

The angles of the claw portions and cutaways in the circumferentialdirection, on the lens mount 1301 and camera mount 1401 provided to thefirst conversion adapter 40, will be compared. For example, at the lensmount 1301 side, the angle θA5 of the second lens cutaway 1301 b havingthe smallest angle is 44°, whereas, at the camera mount 1401 side, theangle θA1 of first camera claw portion 1401 a having the smallest angleis 56°. That is to say, the claw portion having the smallest angle atthe camera mount 1401 side is larger than the cutaway having thesmallest angle at the lens mount 1301 side (θA5<θA1). In this case, ofthe cutaways on the lens mount 1301 side and the claw portions on thecamera mount 1401 side, at least one or more lens cutaway and cameraclaw portions will interfere with each other. Accordingly, even if anattempt is made to mount the interchangeable lens assembly to the camerabody so that the optical axis at the camera mount 1401 side and lensmount 1301 side are generally parallel, the claw portions and cutawaysinterfere, so the interchangeable lens assembly cannot be mounted to thecamera body.

However, if only one claw portion and cutaway are interfering, there maybe cases where claw portions of the camera mount side can be insertedinto cutaways of the lens mount side. FIGS. 19A and 19B are diagramsexemplarily describing a mounting method of a predetermined imagingapparatus 1000 and a predetermined interchangeable lens assembly 2000having claw portions and cutaways that interfere with each other. FIG.15A is a diagram exemplarily describing a frontal view of partwaythrough mounting a predetermined interchangeable lens assembly to apredetermined imaging apparatus that have claw portions and cutawaysthat interfere with each other. FIG. 19B is a cross-sectional view takenalong cross-section XIXB-XIXB in FIG. 19A.

For example, in a state where the optical axis of the lens mount side isobliquely inclined as to the optical axis of the camera mount side, oneend of a camera claw portion is inserted into a lens cutaway, and fromthis state, the lens mount and camera mount are rotated relatively toeach other, as illustrated in FIGS. 15A and 15B. In this case, even ifthe camera claw portions and lens cutaways originally interfere witheach other, this interference with each other is resolved during therelative rotation of the lens mount and camera mount, and transition canbe made to a state where the camera claw portion is inserted into thislens cutaway. In this case, if there are no other camera claw portionsand lens cutaways interfering, the interchangeable lens assembly can bemounted to the camera body.

Accordingly, the claw portions and cutaways on the lens mount 1301 sideand camera mount 1401 side are disposed such that the angle of apredetermined lens cutaway adjacent to a reference lens claw portion issmaller than the angle of two camera claw portions adjacent to areference camera cutaway. Specifically, in the present embodiment, theangles θA4 and θA5 of the first lens cutaway 1301 a and second lenscutaway 1301 b adjacent to the first lens claw portion 1301 d aresmaller than the angles θA1 and θA2 of the first camera claw portion1401 a and second camera claw portion 1401 b adjacent to the firstcamera cutaway 1401 d. That is to say, θA4 (52°) is smaller than θA1(56°), and θA5 (44°) is smaller than θA2 (62°) (θA4<θA1, θA5<θA2).Accordingly, even if an attempt is made to insert the first lens clawportion 1301 d into the first camera cutaway 1401 d, the second lensclaw portion 1301 e interferes with the second camera claw portion 1401b in a sure manner, as well does the third lens claw portion 1301 f withthe first camera claw portion 1401 a, as illustrated in FIGS. 20A and20B.

FIGS. 20A and 20B are diagrams exemplarily describing the way in whichclaw portions interfere with each other when attempting to mount thelens mount 1301 side to the camera mount 1401 side according to theembodiment of the present invention. FIG. 20A illustrates the way inwhich the third lens claw portion 1301 f and the first camera clawportion 1401 a interfere, and FIG. 16B illustrates the way in which thesecond lens claw portion 1301 e and the second camera claw portion 1401b interfere.

As described above, incompatible interchangeable lens assemblies andimaging apparatuses, and the mount portions of conversion adapters areconfigured so that two claw portions of each other out of the clawportions that an incompatible interchangeable lens assembly and imagingapparatus have interfere with each other in the present embodiment.According to this configuration, the risk of an incompatibleinterchangeable lens assembly being erroneously mounted to an imagingapparatus, or an incompatible interchangeable lens assembly and imagingapparatus being erroneously mounted to mount units provided to both endsof a conversion adapter, can be reduced.

However, even in a case where the above conditions are satisfied, theremay be cases where, when attempting to insert three claw portions intoincompatible cutaways, for example, two claw portions are inserted intocutaways depending on the angles of the claw portions and cutaways.Accordingly, the present embodiment further takes a configuration wherethe angles of at least two adjacent lens cutaways are smaller than theangles of all camera claw portions. Specifically, in the presentembodiment, the angles θA4 and θA5 of the first lens cutaway 1301 a andsecond lens cutaway 1301 b in the circumferential direction are smallerthan the angles θA1 through θA3 of the first through third camera clawportions 1401 a through 1401 c in the circumferential direction. That isto say, the relation between the claw portions and cutaways at the lensmount 1301 side and the camera mount 1401 side according to the presentembodiment satisfy θA4<θA1, θA4<θA2, θA4<θA3, θA5<θA1, θA5<θA2, andθA5<θA3.

FIGS. 21A through 21D is a diagram exemplarily describing a case ofattempting to insert incompatible claw portions into cutaways at thelens mount 1301 side and camera mount 1401 side according to theembodiment of the present invention. FIG. 21A illustrates the way inwhich the third lens claw portion 1301 f and third camera claw portion1401 c interfere in a case of attempting to insert the first lens clawportion 1301 d into the third camera cutaway 1401 f. FIG. 21Billustrates the way in which second lens claw portion 1301 e and firstcamera claw portion 1401 a interfere in a case of attempting to insertthe first lens claw portion 1301 d into the third camera cutaway 1401 f.FIG. 21C illustrates the way in which the third lens claw portion 1301 fand second camera claw portion 1401 b interfere in a case of attemptingto insert the first lens claw portion 1301 d into the second cameracutaway 1401 e. FIG. 21D illustrates the way in which the second lensclaw portion 1301 e and third camera claw portion 1401 c interfere in acase of attempting to insert the first lens claw portion 1301 d into thesecond camera cutaway 1401 e.

As illustrated in FIGS. 21A through 21D, the lens claw portions andcamera claw portions interfere in at least two places in the presentembodiment, regardless of the relative rotational angle of the lensmount 1301 and camera mount 1401. According to this configuration,erroneous mounting of an interchangeable lens assembly and conversionadapter having the lens mount 301 (1301) to an imaging apparatus andconversion adapter having the camera mount 401 (1401) can be preventedeven more effectively.

Next, the angles (phases) at which bayonet claw portions are disposed onthe circumferential direction of the camera mount and lens mount of thesecond conversion adapter 70 will be described with reference to FIGS.22A through 26.

The second conversion adapter 70 is a mount adapter used for mountingthe first lens 100 that has a short flange focal distance to the camerabody 60 that has a long flange focal distance. The lens mount 1501 isprovided at one end (third end) side of the second conversion adapter70, and the camera mount 1201 is provided at the other end (fourth end).Note that the camera mount 1201 of the second conversion adapter 70 hasthe same configuration as the camera mount 201 of the camera body 10that is the first imaging apparatus described above. Also, the lensmount 1501 of the second conversion adapter 70 has the sameconfiguration as the lens mount 501 of the second lens 50 describedabove.

Accordingly, it is preferable for the second conversion adapter 70 to beconfigured such that the camera body 10 that has a short flange focaldistance cannot be directly mounted to the lens mount 1501, and thesecond lens 50 that has a long flange focal distance cannot be directlymounted to the camera mount 201. This configuration can be realized bysatisfying the positional relation of claw portions and cutaways so thatthe lens mount 1501 provided to one end (third end) of the secondconversion adapter 70 and the camera mount 1201 provided to the otherend (fourth end) cannot each be directly mounted.

FIGS. 22A and 22B are diagrams exemplarily describing angles ofdisposing bayonet claw portions in the camera mount 1201 provided on oneend of the second conversion adapter 70. FIG. 22A is a diagramillustrating angle ranges that camera claw portions and camera cutawaysoccupy in the circumferential direction of the camera mount 1201 withthe lock pin 202 as a reference, as viewed from the rear face side. FIG.22B is a diagram illustrating angle ranges that, regarding multiplecamera claw portions 1201 a through 1201 c, the claw portions occupy inthe circumferential direction of the camera mount 1201, as viewed fromthe rear face side. Note that the angles of disposing the claw portionsand cutaways on the camera mount 1201 of the second conversion adapter70 are the same as the camera mount 201 of the camera body 10 describedearlier, so description will be omitted.

As illustrated in FIG. 22B, the angle from the sixth end 1201 c 2 of thethird camera claw portion 1201 c to the third end 1201 b 1 of the secondcamera claw portion 1201 b, in the circumferential direction of thecamera mount 1201 including the first camera claw portion 1201 a, is θA6(162°). The angle from the second end 1201 a 2 of the first camera clawportion 1201 a to the fifth end 1201 c 1 of the third camera clawportion 1201 c, in the circumferential direction of the camera mount1201 including the second camera claw portion 1201 b, is θA7 (163°). Theangle from the fourth end 1201 b 2 of the second camera claw portion1201 b to the first end 1201 a 1 of the first camera claw portion 1201a, in the circumferential direction of the camera mount 1201 includingthe third camera claw portion 1201 c, is θA8 (215°).

Next, FIGS. 23A through 23C are diagrams exemplarily describing angle sodisposing bayonet claw portions in a lens mount 1501 provided on theother end of the second conversion adapter 70. FIG. 23A is a diagramillustrating angle ranges that lens claw portions and lens cutawaysoccupy in the circumferential direction of the lens mount 1501 with thelock pin 1501 z as a reference, as viewed from the rear face side. FIG.23B is a diagram illustrating angle ranges where cutaways are providedregarding the multiple lens cutaways 1501 a through 1501 c in thecircumferential direction of the lens mount 1501, as viewed from therear face side. FIG. 23C is a cross-sectional diagram taken alongcross-section XXIIIC-XXIIIC in FIG. 23B.

A first lens claw portion 1501 d, second lens claw portion 1501 e, andthird lens claw portion 1501 f, are provided in order, to the cameramount 1501 in the circumferential direction (inner radial direction).Note that in a case of viewing the lens mount 1501 from the rear faceside as illustrated in FIG. 23A, the lens claw portion that is providedat a position farthest from the lock groove 1501 z is the first lensclaw portion 1501 d. The second lens claw portion 1501 e and third lensclaw portion 1501 f are then consecutively provided in order from thefirst lens claw portion 1501 d in a clockwise direction.

Also, cutaways which are a first lens cutaway 1501 a, second lenscutaway 1501 b, and third lens cutaway 1501 c are provided in order, tothe lens mount 1501 in the circumferential direction (inner radialdirection). Note that in a case of viewing the lens mount 1501 from therear face side as illustrated in FIG. 23A, the cutaway that is providedat a position nearest to the lock groove 1501 z is the third lenscutaway 1501 c. The first lens cutaway 1501 a and second lens cutaway1501 b are then consecutively provided in order from the third lenscutaway 1501 c in a clockwise direction.

Note that the end portions of the lens claw portions 1501 d, 1501 e, and1501 f, in the circumferential direction, will be referred to as firstend portion 1501 d 1, second end portion 1501 d 2, third end portion1501 e 1, fourth end portion 1501 e 2, fifth end portion 1501 fl, andsixth end portion 1501 f 2, for the sake of description. The endportions are denoted with part numerals in order from the first lensclaw portion 1501 d in the clockwise direction, when viewing the lensmount 1501 from the rear face side, as described above.

As illustrated in FIG. 23A, the angles that the lens claw portions andlens cutaways occupy in the circumferential direction of the lens mount1501 (angle ranges) are stipulated as follows. The angle of the firstlens claw portion 1501 d is 53°, the angle of the second lens clawportion 1501 e is 62°, and the angle of the third lens claw portion 1501f is 53°. That is to say, the angles of the lens claw portions on thelens mount 1501 side are the same as the angles of the lens clawportions on the lens mount 1301 side described earlier.

On the other hand, the angles of the lens cutaways at the lens mount1501 side differ from the angles of the lens cutaways at the lens mount1301 side described above. Specifically, the angle of the first lenscutaway 1501 a is 60°, the angle of the second lens cutaway 1501 b is66°, and the angle of the third lens cutaway 1501 c is 66°.

Also, when viewing the lens claw portions from the rear face side of thecamera body 10, the angles in the clockwise direction where the lensclaw portions are disposed on the circumferential direction of the lensmount 1501 with the position of the lock groove 1501 z (referred to asreference position) as a reference are stipulated as follows. The firstlens claw portion 1501 d is disposed between 157° to 210° with thereference position as a start point. The second lens claw portion 1501 eis disposed between 276° to 338° with the reference position as a startpoint. The third lens claw portion 1501 f is disposed between 44° to 97°with the reference position as a start point.

As illustrated in FIG. 23C, a fitting member 1501 x that restrictsmovement of the imaging apparatus in a direction parallel to the opticalaxis when mounted to the imaging apparatus is provided to the lens mount1501 side. In the present embodiment, the diameter of the fitting member1501 x in a direction orthogonal to the optical axis at the camera mount1501 side is the mount diameter. The mount diameters of the cameramounts and lens mounts described above are generally the same length.

As illustrated in FIG. 23B, the angle from the fifth end 1501 fl of thethird lens claw portion 1501 f to the second end 1501 d 2 of the secondlens claw portion 1501 d, in the circumferential direction of the lensmount 1501 including the first lens cutaway 1501 a, is θA9 (166°). Theangle from the first end 1501 d 1 of the first lens claw portion 1501 dto the fourth end 1501 e 2 of the second lens claw portion 1501 e, inthe circumferential direction of the lens mount 1501 including thesecond lens cutaway 1501 b, is θA10 (181°). The angle from the third end1501 e 1 of the second lens claw portion 1501 e to the sixth end 1501 f2 of the third lens claw portion 1501 f, in the circumferentialdirection of the lens mount 1501 including the third lens cutaway 1501c, is θA11 (181°).

The angles of the claw portions and cutaways in the circumferentialdirection will be compared between the camera mount 1201 and lens mount1501 provided to the second conversion adapter 70. For example, theangle (92°) of the third camera claw portion at the camera mount 1201side is larger than the angles (66°) of the second and third lenscutaways 1501 b and 1501 c that are the largest angle of the lenscutaways at the lens mount 1501 side. That is to say, the angle of atleast one camera claw portion at the camera mount 1201 side is largerthan the angle of the lens cutaway having the largest angle at the lensmount 1501 side.

In this case, of the claw portions at the camera mount 1201 side andcutaways at the lens mount 1501 side, at least one or more camera clawportion and lens cutaway interfere with each other. Accordingly, even ifan attempt is made to mount the interchangeable lens assembly to thecamera body so that the optical axis at the camera mount 1201 side andlens mount 1501 side are generally parallel to each other, the clawportions and cutaways interfere, so the interchangeable lens assemblycannot be mounted to the camera body.

However, if only one claw portion and cutaway are interfering, there maybe cases where claw portions of the camera mount side can be insertedinto cutaways of the lens mount side, in the same way as the descriptionof the first conversion adapter made above. For example, there are caseswhere, in a state where the optical axis of the lens mount side isobliquely inclined as to the optical axis of the camera mount side, oneend of a camera claw portion is inserted into a lens cutaway, and thelens mount and camera mount are rotated relative to each other, and theinterchangeable lens assembly can be mounted to the camera body.

Accordingly, in the present embodiment, the claw portions and cutawaysat the camera mount 1201 side and the lens mount 1501 side are disposedso as to satisfy θA6<θA9 and θA7′<θA10 in the circumferential direction.FIGS. 24A and 24B are diagrams exemplarily describing the way in whichclaw portions interfere with each other, when attempting to mount areference claw portion at the lens mount 1501 side to a referencecutaway at the camera mount 1201 side according to the embodiment of thepresent invention. FIG. 20A illustrates the way in which the third lensclaw portion 1501 f and the third camera claw portion 1201 c interfere,and FIG. 20B illustrates the way in which the second lens claw portion1501 e and the third camera claw portion 1201 c interfere.

As illustrated in FIGS. 24A and 24B, in a case where the reference firstlens claw portion 1501 d is attempted to be inserted into the referencecamera cutaway 1201 d, for example, the third camera claw portion 1201 cinterferes with the second and third lens claw portions 1501 e and 1501f.

That is to say, as viewed from the rear face side, the total sum of theangles of one reference lens claw portion, another lens claw portionadjacent thereto in the clockwise direction, and a lens cutaway situatedbetween these lens claw portions, is taken as a first angle. Also, asviewed from the rear face side, the total sum of the angles of onereference camera cutaway, another camera cutaway adjacent thereto in theclockwise direction, and a camera claw portion situated therebetween, istaken as a second angle. Also, as viewed from the rear face side, thetotal sum of the angles of one reference lens claw portion, another lensclaw portion adjacent thereto in the counterclockwise direction, and alens cutaway situated between these lens claw portions, is taken as afirst angle. Also, as viewed from the rear face side, the total sum ofthe angles of one reference camera cutaway, another camera cutawayadjacent thereto in the counterclockwise direction, and a camera clawportion situated therebetween, is taken as a fourth angle. According tothe present embodiment, it is sufficient to layout the claw portions andcutaways at the camera mount 1201 side and lens mount 1501 side suchthat the first angle described above is larger than the second angle,and the third angle is larger than the fourth angle.

According to this configuration, at least two lens claw portions and onecamera claw portion interfere with each other. Thus, the risk of anincompatible interchangeable lens assembly being erroneously mounted toan imaging apparatus, or an incompatible interchangeable lens assemblyand imaging apparatus being erroneously mounted to mount units providedto both ends of a conversion adapter, can be reduced.

However, even in a case where the above conditions are satisfied, theremay be cases where, when attempting to insert three claw portions intoincompatible cutaways, for example, two claw portions are inserted intocutaways depending on the angles of the claw portions and cutaways.Accordingly, the claw portions and cutaways at the camera mount 1201side and lens mount 1501 side are disposed in the circumferentialdirection so as to satisfy θA6<θA9, θA6<θA10, θA6<θA11, θA7<θA9,θA7<θA10, and θA7<θA11. That is to say, as viewed from the rear faceside, the total sum of the angles of two claw portions other than thereference claw portion described above, and a lens cutaway situatedtherebetween, is taken as a fifth angle. According to the presentembodiment, it is sufficient to layout the claw portions and cutaways atthe camera mount 1201 side and lens mount 1501 side such that the secondangle and fourth angle described above are smaller than any of the firstangle, third angle, and fifth angle.

FIGS. 25A through 25D are diagrams exemplarily describing the way inwhich claw portions interfere with each other, when attempting to mounta claw portion other than the reference claw portion at the lens mount1501 side to a reference cutaway at the camera mount 1201 side accordingto the embodiment of the present invention. FIG. 25A illustrates the wayin which the first lens claw portion 1501 d and the third camera clawportion 1201 c interfere in a case of attempting to insert the secondlens claw portion 1501 e into the first camera cutaway 1201 d. FIG. 25Billustrates the way in which the third lens claw portion 1501 c and thethird camera claw portion 1201 c interfere in a case of attempting toinsert the second lens claw portion 1501 e into the first camera cutaway1201 d. FIG. 25C illustrates the way in which the second lens clawportion 1501 e and the third camera claw portion 1201 c interfere in acase of attempting to insert the third lens claw portion 1501 f into thefirst camera cutaway 1201 d. FIG. 25D illustrates the way in which thefirst lens claw portion 1501 d and the third camera claw portion 1201 cinterfere in a case of attempting to insert the third lens claw portion1501 f into the first camera cutaway 1201 d.

As illustrated in FIGS. 25A through 25D, at least two lens claw portionsand one camera claw portion interfere, regardless of the relativerotation angle of the lens mount 1501 and camera mount 1201 according tothe present embodiment. According to this configuration, erroneousmounting of an interchangeable lens assembly and conversion adapterhaving the lens mount 501 (1501) to an imaging apparatus and conversionadapter having the camera mount 201 (1201) can be prevented even moreeffectively.

FIG. 26 is a diagram exemplarily describing a state in which clawportions provided to the camera mount 1401 side and lens mount 1501 sideaccording to the embodiment of the present invention are engaged. Notethat FIG. 26 illustrates a state in which the camera mount 401 of thecamera body 60 is engaging with the lens mount 501 of the second lens50. The first lens claw portion 1501 d can be inserted into the firstcamera cutaway 1401 d, as illustrated in FIG. 22. Also, the second lensclaw portion 1501 e can be inserted into the second camera cutaway 1401e. Further, the third lens claw portion 1501 f can be inserted into thethird camera cutaway 1401 f. That is to say, the camera mount 1401 sideand the lens mount 1501 side are a combination compatible with beingdirectly mounted to each other. Note that the camera mount 201 side andthe lens mount 301 side are a combination compatible to being directlymounted to each other, as illustrated in FIG. 10A.

As described above, the camera mount 401 (1401) corresponding to animaging apparatus that has a long flange focal distance (e.g., thecamera body 60), and the lens mount 501 (1501) corresponding to aninterchangeable lens assembly that has a long flange focal distance(e.g., the second lens 50) can be directly mounted to each other.However, the camera mount 201 (1201) corresponding to an imagingapparatus having a short flange focal distance (e.g., the camera body10) and the lens mount 501 (1501) corresponding to an interchangeablelens assembly that has a long flange focal distance (e.g., the secondlens 50) cannot be directly mounted to each other. Also, the cameramount 201 (1201) corresponding to an imaging apparatus that has a shortflange focal distance (e.g., the camera body 10) and the lens mount 301(1301) corresponding to an interchangeable lens assembly that has ashort flange focal distance (e.g., the first lens 100) can be directlymounted to each other. However, the camera mount 401 (1401)corresponding to an imaging apparatus that has a long flange focaldistance (e.g., the camera body 60) and the lens mount 301 (1301)corresponding to an interchangeable lens assembly that has a shortflange focal distance (e.g., the first lens 100) cannot be directlymounted to each other.

Accordingly, an imaging apparatus and camera accessory employing theconfiguration of the above-described embodiment can prevent erroneousmounting of an imaging apparatus and camera accessory that havegenerally the same mount diameter but are not mutually compatible.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments.

What is claimed is:
 1. A lens mount configured to be detachablymountable to a camera mount, wherein the camera mount includes aplurality of first bayonet claw portions and a plurality of firstterminals, the lens mount comprising: a plurality of second bayonet clawportions configured to allow engagement with the plurality of firstbayonet claw portions; and a plurality of second terminals configured tocontact with the plurality of first terminals when the lens mount ismounted to the camera mount, wherein the plurality of second terminalsis provided at positions that are different from positions of theplurality of second bayonet claw portions, wherein the plurality ofsecond terminals includes a MIF terminal used in determination whetherthe lens mount is mounted on the camera mount, the determination beingtrigger that start supply of power from the camera mount to the lensmount, and wherein, when viewed in a central axis direction of the lensmount, a half line, that extends from a central axis of the lens mountand passes through the MIF terminal, passes through a predeterminedbayonet claw portion among the plurality of second bayonet clawportions.
 2. The lens mount according to claim 1, wherein the pluralityof second terminals includes a plurality of communication terminalsconfigured to be used in communication between the camera mount and thelens mount, and wherein, when viewed in the central axis direction, aplurality of half lines, that extends from the central axis and passesthrough the plurality of communication terminals, all pass through thepredetermined bayonet claw portion.
 3. The lens mount according to claim1, further comprising a terminal holding portion configured to hold theplurality of second terminals, wherein the terminal holding portionincludes a positioning portion to determine position of the terminalholding portion with respect to the plurality of second bayonet clawportions.
 4. The lens mount according to claim 3, wherein, when a firstadjacent terminal is a terminal adjacent to the MIF terminal on one sidewith respect to the MIF terminal, a second adjacent terminal is aterminal adjacent to the MIF terminal on the other side with respect tothe MIF terminal, and a third adjacent terminal is a terminal adjacentto the second adjacent terminal, and wherein, when viewed in the centralaxis direction, the positioning portion is inside a first region betweena half line that extends from the central axisand passes through thefirst adjacent terminal, and a half line that extends from the centralaxis and passes through the third adjacent terminal.
 5. The lens mountaccording to claim 4, wherein, when viewed in the central axisdirection, the positioning portion is inside a MIF region between a halfline that extends from the central axis and passes through the MIFterminal, and the half line that extends from the central axis andpasses through the third adjacent terminal.
 6. The lens mount accordingto claim 3, wherein, when viewed in the central axis direction, a halfline that extends from the central axis and passes through thepositioning portion passes through the predetermined bayonet clawportion.
 7. The lens mount according to claim 1, wherein the pluralityof second terminals include a TYPE terminal configured to be used todistinguish a type of the lens mount mounted on the camera mount.
 8. Thelens mount according to claim 7, wherein, when viewed in the centralaxis direction, a half line, that extends from the central axis andpasses through the TYPE terminal, passes through between the pluralityof second bayonet claw portions.
 9. The lens mount according to claim 8,wherein the plurality of second terminals includes a terminal configuredto connect the camera mount and a communication control system of thelens mount to ground, and includes a terminal configured to supplypower, to be used in an operation of the communication control system,from the camera mount to the lens mount.
 10. The lens mount according toclaim 9, wherein the plurality of second terminals includes a terminalconfigured to connect the camera mount and a mechanical drive system ofthe lens mount to the ground, and includes a terminal configured tosupply power, to be used in the operation of the mechanical drivesystem, from the camera mount to the lens mount.
 11. The lens mountaccording to claim 10, wherein the plurality of second terminalsincludes a first communication unit configured to perform a firstcommunication, and wherein the first communication unit includes: aterminal configured to communicate a clock signal that is output fromthe camera mount to the lens mount, a terminal configured to allowtwo-way communication between the camera mount and the lens mount, and aterminal configured to communicate a data that is output from the lensmount to the camera mount.
 12. The lens mount according to claim 11,wherein the plurality of second terminals includes a secondcommunication unit configured to perform a second communicationindependent of the first communication performed by the firstcommunication unit, and wherein the second communication unit includes asecond terminal configured to communicate the data that is output fromthe lens mount to the camera mount.
 13. The lens mount according toclaim 12, wherein the plurality of second terminals includes a thirdcommunication unit configured to perform a third communication that isindependent of the first communication and the second communication, andwherein the third communication unit includes: a terminal configured toallow two-way communication between the camera mount and the lens mount,and a terminal configured to communicate a communication request signalbetween the camera mount and the lens mount.
 14. An accessorycomprising: the lens mount according to claim 1; and a lens.
 15. Anaccessory comprising: the lens mount according to claim 1; and aplurality of third bayonet claw portions configured to allow engagementwith a plurality of bayonet claw portions of a lens apparatus.
 16. Acamera mount comprising: a plurality of first bayonet claw portions; anda plurality of first terminals, wherein the camera mount is configuredsuch that the lens mount according to claim 1 is detachably mountable tothe camera mount.
 17. A camera system comprising: the lens mountaccording to claim 1; and a camera mount, wherein the camera mountincludes: a plurality of first bayonet claw portions, and a plurality offirst terminals, and wherein the camera mount is configured such thatthe lens mount is detachably mountable to the camera mount.
 18. An imagepickup apparatus comprising: an image pickup element; and a cameramount, wherein the camera mount includes: a plurality of first bayonetclaw portions, and a plurality of first terminals, and wherein thecamera mount is configured such that the lens mount according to claim 1is detachably mountable to the camera mount.